On the list of current athletes, I'd have to say he's near the top if not #1. The only other one that even competes with him in terms of sheer dominance would be Michael Phelps who has no equal in the water just as Tiger has none on the golf course. It could be argued that Roger Federer was up there before the rise of Rafael Nadal, but that is no longer the case. Nadal himself may soon find himself in the discussion though.
Now what I like to think about it where he ranks on the all-time list of athletes. I think most would agree that Tiger is the best golfer ever even if he retires right now and never gets the record for majors. Jack Nicklaus was great and a true legend, but I think all-around Tiger is better and it's really not that close. Now you have to look at some other dominant athletes that we have seen in various sports..
Michael Jordan, Wayne Gretzky, Pele, Babe Ruth, Muhammad Ali, Wilt Chamberlain, Pete Sampras, Jim Brown, Richard Petty, Sugar Ray Robinson, and for the sake of this being a wrestling forum we'll include Hulk Hogan.
I think all of these guys have a case and I won't even try to rank them as it would require more thought and research than I have time or patience for, but Tiger's name definitely belongs among them. Where exactly is debatable. The rest of these guys dominated their respective sports like no other as well. Now transcending just sports some of these other guys did much to give than just to their sports. Not that Tiger doesn't, but he often doesn't want to be viewed in a bad light so he doesn't speak on controversial issues..he just does he thing, his endorsements, and gives to charities but that's all. Nothing is wrong with that, but the issue has to be included.
All that being said, I think Tiger's name belongs right along with the top 3-5 athletes of all-time, or at least it will by the time his career is over. Some of these other guys set records that for their time were incredible, but most of which will be broken (other than some of Gretzky's which may never be). Tiger imo, will completely obliterate all the major golf records and sure there could be another, but I just don't think anyone will be able to even sniff his records much less break them. So for that he belongs in the top echelon of great athletes.