I can't find the figures anywhere so I thought I'd try here. Who has more users,

I can back it up with facts because I work at Yahoo!. Last month Yahoo!'s mail became the largest in the world, surpassing Hotmail for the first time. Gmail is currently either 3rd or 4th. Yahoo! Beta mail will be coming out early next year. Although I haven't use it yet, it's claimed that it will blow everyone away. (Don't know if that's just internal hype or actually backed up with stats, but some of the features sound really cool.)