PS3 hands down better in every way. Xbox has such a bad record of RROD.
PS3 you can upgrade the HDD size to what ever size you want, they are just laptop drives, sony encourges this.
Sony playstation network is free!!!!!!!!!!!!!!
You can use your PS3 as a media server, it will become the hub of the lounge.
BLURAY!!! got a HD TV, then you can watch blurays on your ps3
3D BLURAY, have you got a 3d TV, well the ps3 can output two channels of 1080p so that you get the full 3D expieiance.
The PS3 is so clever you can now play a 2 player game which would normally be split screen with 3D glasses and each player will now see his screen only in full screen! amazing
PS3 has some amazing titles.
Kinect is ok, but is kinda boring, playstation invented it back on the PS2 with the eyetoy.
Put all your favourite photos, movies and music on your PS3, if you have Vita or PSP you can stream them to your device anywhere in the world.
PS3 controllers are bluetooth and far superior