I already have a Sony Bravia and PS3 and I can tell you without a shadow of a doubt that the difference is huge. The detail and clarity of image are amazing, and blacks actually look ‘black’.
I would plump for the PS3 if I were you, basically the PS3 is a better bluray player than most standalone bluray players. To get the same standard at the moment you would have to spend over £600. Oh, yeah, and some of the games are good too, and you can play PS1 games on them!