not a pro, but close
With all this poker talk, i've got to weigh in. I've been playing online poker practically since its inception. I'm talking about being on Party Poker when the site had less than 300 people, now it pushes 80,000 every day. During that time, I've studied and improved, regressed and studied again, and on and on.
Overall, I'm up a decent amount though I generally play low to medium limit games. I've played over 20 different sites and I can tell you that collusion does happen. That said, if you play properly and understand your opponents and your cards, you can reliably win in the LONG RUN. If you're not willing to work to master the game, then forget it. The rake will kill you along with the luck factor.
I'm not saying I'm a master, by any definition, but I have a lot of experience playing online 1/2, 2/4, 5/10, 20/40, limit, no-limit, tourneys, hold'em, stud, omaha, pineapple.... the list goes on. I know a lot of guys who make this a professional proposition and do well. It's a tough life and you gotta grind it out, but the possibility is there.
Check out a couple of sites and tools if you're interested in getting to the next level...
www.twoplustwo.com - best poker forum on the net.
www.pokertracker.com - one of the better stat engines for tracking your play.