[Nate tha' Great]

Again, it depends on what sort of graduate program you're looking at.

I'd think that the 'gap' would be almost as devasting from the standpoint of a top-tier business school as for a top-tier employer. Perhaps even more so. Although frankly I think business school is fairly worthless and have had some Very Smart People who have been to some Very Good Business Schools tell me as much.

Law schools tend to be highly numbers and formula-oriented and if your LSATs and undergraduate credentials are good, I don't think you'd have too much trouble.

Masters programs are cash cows at most univerisities and will let you in if you're smart and can foot the bill.

PhD programs - I had a friend who was recently asked to join a very selective PhD track in spite of essentially having been a professional alcoholic for about seven years out of undergrad. Surely being a professional poker player isn't quite as bad as that. You do need to write/present well though in a wonky sort of way.

EDIT: I'm not any kind of career counselor, although I do happen to have an odd diversity of friends/acquaintences who have taken an oddly diverse array of career tracks. I've also been on both sides of the interviewee/interviewer process, the later half of which is extremely helpful.