Palringo have announced they will be releasing an IM application supporting MSN, ICQ, AIM, Y, GTalk, Jabber, GG.
It's not available on the App Store right now though.
it will be a shame if no one does put one out
Just so I'm clear -- If i'm using the AIM client, and I open something else (ie. mail or safari), I will NOT receive any notification that I received any IMs until I open AIM again? Does it even show any number indicator (badge) next to the AIM icon before I open it?