I really think we're making too big a deal of this. The "general public" already deals with this in $. Ex: $50B. $50M. $50K. $50. 50 cents. we choose the appropriate units depending on the amount. I'm sure people will figure out how to do the same with bitcoin.
I understand your point, but the billion/million/thousand specifiers aret (relatively unknown) descending SI units in an currency looking for recognition. Most people still can't differentiate between megs and gigs on their smartphone. Ask a hundred people on the street which is worth more, a BTC, mBTC or uBTC and I'll be surprised if more than 10% even notice that mBTC != uBTC.
To that end, doesn't it make sense to start using mBTC as the standard unit now, since that's the way the world will be headed if BTC/USD price continues to rise?