I think in the near future when BTC has widespread acceptance but still rests secondary among default government fiat, most normal users won't care about how many decimal places it has. Chances are the default display on whatever the payment interface will read out in the currency denomination of the legal tender of the users choice.

Example:
You go to McDonalds to buy a McDouble for $1 but you choose to pay with BTC. You just scan the QR code or link by some other means to the McDonalds cash register and the amount is automatically displayed on your device to be withdrawn. You just enter your PIN number to verify the transaction and everything else is automatic. You don't know the current exchange rate but you know that $1 was spent and you can check your balance to see what you have left.

In the future future (assuming Bitcoin survives) it will probably be worth enough that ordinary transactions will be in the few hundreds of Satoshi's and it will be displayed as such. If you have 10,000 satoshis you can pay your rent.

Ignore lists are for amatures

The smallest denomination should probably be the same as the fee to send. So .0001 would be the smallest decimal place.

But when Bitcoin is worth $100 million per coin that would mean the smallest denomination is worth $100,000 and it costs that much just to send a transaction. lol

childish last thing we need here

Nobody is forcing anybody to use the clients that are out there. If you want mBTC (which is already in the bitcoin-qt) to be named BTC fork the client and publish it and let's see how many people use it. I don't see a problem.

I howerever, like many others I'm sure, will continue to use metric prefixes as that makes perfect sense to the majority of the world.

If Bitcoin fails to understand users, it will become the next "Year of Linux Desktop".

I think the safest way, to avoid economic corruption, is to keep it as is.