I'm actually shocked at the number of people commenting here in the last week or so who seem to think that Yahoo! owes them something. Have you ever read the fine print on PokerStars? Do THAT math. I'll bet they're making $3,500,000 a day! I'm not joking. They take a small rake/percentage of every real money hand played.
Not sure how people could be complaining about this for a week as Pro leagues opened yesterday.
But i get your point, and i have no problem with them taking something, but i'd say 15% is solid enough - standard agency fee makes sense to me. and honestly, it might cause more people to participate thus bringing in more revenue for Yahoo!