Proud XCP bagholder here (I'm an original burner, in fact). The Counterparty developers have an amazing track record, and it's clear their platform is just getting warmed up. The Ethereum devs, well, it's too soon to tell but Q1 2015 is proving to be a long time to wait in crypto land. First mover advantage is the rule (although by that rule, Mastercoin should have done better).
XCP may be the only truly deflationary currency out there, so I think it would be good to pick up a few coins just in case it takes off.

Congratulations on your early horse - beautifully backed. That is an incredible return.
Thinking of the future though, the thing about what Vitalic said - it rang lots of bells with me.
It's also the reason why I like DRK - it is a dedicated solution, like Apple. They make the hardware, they make the software. Square pegs in round holes can work (SQL was a command language that got rammed down the throats of programmers by Microsoft who somehow got away with selling it as a "programming language", Windows was a clunky GUI that converted mouse movements into DOS commands) but they are never very elegant.
Counterparty seem to have taken 2 technologies that have absolutely nothing to do with each other and decided to weld them together. When you do that what you usually end up with is the lowest common denominator - a totally crap result that is less than the sum of its parts. Another thing that's weird is - why did they wait till now to introduce the Etherium thing ? Was that an afterthought?
I'm not trying to "FUD" you or anything - that rise is literally off the charts - but the recipe doesn't exactly sound promising to me from the point of buying into an all time high. Look at the amount of work its taken 100% proprietary projects like Darkcoin or NxT to even get established with their core technical objectives, and thats when they have control over everything. What then when you neither have any control over the blockchain architecture nor the intelligent stuff that's riding on top of it ?
Because that's what so much open-source software is about. There is a book called "The Unix Philosophy", since revised to be called "The Linux Philosophy". It is all about keeping things atomic - having a piece of software do one thing, and do that thing really well, and allow it to connect to other things.
It is kind of like the concept of a pipe ("|" character) in the command line. You can have one program run, and send the results to another program, and send those results to another program -- all of those programs run completely separately, but by having well-defined interfaces, they can be connected together in myriad ways to create even more powerful "programs" out of the smaller ones.
Or take the Web. It is based on a series of protocols, each independent of each other but building on the one below it. You have HTML, which rides on top of HTTP, which rides on top of TCP/IP, which rides on top of mostly Ethernet-based hardware. Each of those layers enables the ones above it to work properly. If somebody were to come up with the Web and try to implement it from scratch from the top down, it would never have gotten built in this way; but it might not have ever gotten built at all. Instead, somebody came up with the hardware, then somebody came up with TCP/IP, then somebody came up with HTTP, then somebody came up with HTML. (And then somebody came up with JavaScript...)
It's a way of not re-inventing the wheel. "NIH" (Not Invented Here) Syndrome is a horrible thing in the tech world. Programmers are very arrogant and would rather build their own thing from scratch than re-use somebody else's perfectly workable code and get a jump start. So they end up taking 5 years to create their own from-the-ground-up software instead of 2 years to create something on somebody else's platform.
Why re-invent the blockchain and the mining process (a la NXT, BitShares, Ethereum, Ripple, etc.) when you can just ride on top of the most secure blockchain in existence? Why go to all that work? Yes, you give up some control. But, you can work around that and be finished in months when your competitors take years. Elegance be damned, first-mover advantage is huge and the software that has been released for 2 years and been through many cycles of end-user feedback and improvement will be light years ahead of the elegantly-architected solution that just came out today.
The Ethereum thing was kinda/sorta an afterthought. Counterparty has had support for smart contracts since its inception -- that's kind of whole the idea. But the smart contracts had to be built into the Counterparty protocol itself. E.g. a contract for difference, or a contract for a bet based on a feed, or an escrow (which is effectively what a bet is -- 2 parties contribute their amounts to a 3rd party, and the 3rd party pays the winner based on the result -- in Counterparty, this bet can be enforced.) But Ethereum has been working on developing a language for describing smart contracts so that ANYBODY can create arbitrary smart contracts on the Ethereum platform; and Counterparty took that language and integrated it into Counterparty. So smart contracts that will work in Ethereum when it is released, will also work in Counterparty. So that's what the Ethereum announcement today was about.
A smart contract can also be a purchase or sell order in an exchange. This is how the Counterparty Assets are built. I can make an asset that represents a share in a company, for example (legalities notwithstanding). I can sell that share to somebody else by offering it at a given price. This offer is noted in the blockchain and is enforced by the Counterparty protocol. If somebody else comes along and places a buy order that matches my sell order, the protocol matches the two, I receive my money (XCP or BTC) and the buyer receives the share of stock. My share is effectively escrowed by the protocol when I place the sell order, and the buyer's XCP is effectively escrowed when they place the buy order. The protocol matches the orders and releases the escrows. All of this is done trustlessly. It is a true decentralized exchange. (Of course, you have to trust *somebody*.... e.g. if you're buying shares in my company, you need to trust that I'm who I say I am, and that I will pay dividends etc. But that can be taken care of elsewhere. I can publish my information and the information about the company, and sign a message from the asset-issuing XCP address proving that I own that address.)
Now, it is a truly decentralized exchange. Now how do you trade cryptocurrencies on it? This gets a little harder, and again requires some trust. Say that I have 200 DRK. I put those DRK into an address and publish that address, and create the "XCPDRK" asset on Counterparty which is pegged to the price of DRK at 1:1. So people can trade "XCPDRK" as if it were actual DRK. Theoretically they could cash in their XCPDRK for real DRK on the DRK blockchain, but ideally that would never happen because it would be time-consuming.
This is already happening in some ways. There is an asset issuer that has issued gold-backed assets on the Counterparty Decentralized Exchanged (usually called the DEx). They took photos of the gold bars and put them into storage with a well-known gold storage company. You can buy and sell the gold-backed assets and trade them against BTC and XCP on the Counterparty DEx. And if you choose to, you can redeem your DEx gold-backed assets for actual gold for a fee, and you can come and pick it up in person.
So I hope that illuminates the Counterparty world for you. It would theoretically be easy to fork Counterparty to run on DRK (it has already been cloned on Litecoin, Dogecoin, and Viacoin, among possibly others), but it might have weird interactions with the Masternodes and Darksend... it would probably take a while to be verify that everything works as it should, and it might require a bit of adaptation. But honestly I am surprised that nobody has yet announced a Darkparty implementation. The biggest problem would be getting it off the ground by distributing the tokens (DRKP?) since it is essentially an arbitrary thing.... no mining required.