PS3. I never really spend much time online, when I did go online I never had an issue. The PS3 is the superior console, in my opinion, if you want to boil it all down to hardware and convenience. I wouldnt want to have to use 2 discs to run a game and with the bluray capable of fitting 50gb of content, and with the compression technology if it ever came to that, its less of a hassle than running it on a console that uses a disc with less space available.
I am expecting small differences between console versions, i honestly do think the PS3 will come out on top out of the two. Thats not including the, more than likely, multi disc.