Already there are pictures and gifs on there showing adult content, racism, violence and references to pedophilia.
If you know the origins of memes then this isnt that surprising but for Yahoo to make a site about them is just asking for trouble.
Give it time and there will be a tidal wave of sick material posted on there.
Its funny that in the TOS they mention that none of the material should be offensive in any way but the whole idea of a meme is to be offensive, and or not limited by anything.
Maybe Yahoo saw the whole meme thing on the net and thought to themselves, hey all the cool kids are doing this meme thing lets make a site and hope it becomes popular, This is so gonna backfire on them.