woah I started this thread in '06 and now there are 48 pages?
It's funny because I did well from poker, but nowadays at least online the edge is much smaller. The effort required to be profitable at a decent level us so large that in most cases it's not worth it. There are better ways to make money than poker, so my advice as someone who played semi-professionally for eight years is just keep it casual. This is coming from a profitable poker player.
Advice to anyone reading who's considering online poker as a main source of income:
I'm assuming you live in a 1st world country. You really need to be crushing mid-stakes and be a proven winner for poker to (maybe) be worth pursuing. That is very fucking hard to achieve in 2012. The reason is that people forget about the things they are sacrificing when they get involved in this game. Even if you are a winning player 4-tabling 400nl at 5 ptbb/hr or whatever earning sick hourly rates in the $100s, it's still not good enough. The point is - do you have what it takes to move up? Poker is volatile - in 2008 legislation forced pros in the US to quit. The game is always changing. These are just two examples.
Your poker hourly rate isn't comparable to a true work hourly rate, this is important to understand.
This is a generalisation though - if you have no other options or are sure you have what it takes, then go for it. But for the overwhelming majority of people: do something else, play live, learn some skills etc - there is higher Ev elsewhere and easier money to be made.
Poker pros making far more money than midstakes regs have quit because of this fact. See: timex, shaun deeb.