Perception matters. I've been telling some people I know about bitcoin, and the $800/unit price holds them back mentally. They are reluctant to buy, not because they don't like the idea of the technology or think it has potential, but only because of the high price per unit. They compare it in their minds to the prices of stocks they buy. Nobody wants to buy a fractional share of something. The average small investor might be happy to buy 250 mBTC of bitcoin, but would not bother to buy 0.25 BTC because it feels like a ridiculously small and meaningless amount.
Freebird, your point is valid from a certain point of view, because perception matters indeed - but you need to realize that this talk has been going on sice we first broke $10. At $10, a lot of people said that "internet magic money" that costed $10 "felt too expensive", as we just hit a psychological barrier - so the denomination should change to allow further growth. Same thing happened at $100, just use the seatch function on this forum: you will find many many posts as yours written when we hit $100, and those posts said that $100 was definitely a psychological barrier and "nobody" was going to want to buy a virtual coin for 100 hard earned dollars.
Well.... What happened then?
While I think that the psychological factor has its importance, I'm pretty sure that you are overestimating that importance. Denomination really needs to be something based on convenience - people will naturally switch to mBTC because it will be much more convenient to price items in mBTC... But there's really no need for exchanges to list the price in mBTC, that "psychological barrier" is something that noobs feel when they bought in recently and saw how fast the price rised, so they think that the denomination need to change for the people to keep buying... And that's just a fallacy that has been refuted by history.