It'd be interesting to see some bets/predictions on Lightning Network. I'm interested more in the probability than actual betting (as I'm not that knowledgible about how it is working). Questions like
-will the Ligthning Network be hacked?
-will the beta Lightning Network be hacked? (people are using real money on it while it is in beta or perhaps even alpha)
-when will the Lightning Network come online?
It'd also be interesting to see some bets about Tether. There are rumors floating around that Tether isn't backed by USD and that they are just being printed. It's also possible that the US (or other regulators) will shut it down. Will any of the Tether using exchanges stop using it? Will any of them go into bankruptcy (of couse this could be due to hacking)?
Both of these factors play a key role in the future of Bitcoin (and its price).
I'd like to see some Lightning Network markets, I know what I'll be betting on

).
As for Tether and the rumors.. They are just that - rumors. I believe it floated around for a while but the team behind Tether pulled through and came up with evidence proving that they are solid. They are like USD but for crypto people, which is nice to have, to me at least.