Get an accountant. There are a lot of issues around filing as a professional gambler. The IRS has a history of treating gambling differently than other home businesses and denying most people with jobs the right to file as a pro.
If you don't file as a pro, the only thing you can take as an itemized deduction on Scedule A is the total amount of your losing sessions (your winning sessions go as *other income* on Form 1040).
The main issue here is that if you normally do not itemize, you lose your standard deduction which in effect overstates your poker income by approx. $6,000. If you normally do itemize, the main issue is the fact that you cannot net wins-losses means you overstate your AGI which in some cases impacts your ability to contribute to a Roth IRA *and* potentially introduces the specter of the evil "Alternative Minimum Tax."
But, even though I got an A in Tax Accounting in Grad School, I am neither an accountant, nor do I play one on TV. I didn't even sleep in a Holiday Inn Express last night.
