To understand the differences between PlayStation Home and Second Life, first you have to look at the reason behind the existence of both virtual places.
Second Life is a large virtual world where the majority of the content in the game is generated by the user. Linden Labs lays the groundwork, so to speak, but nearly everything you see while wandering about Second Life came from the mind of one of the game's residents, from clothes and hair to buildings and vehicles...a Second Life resident not only created it, they've probably made a bit of cash off of it as well. It's a living, breathing world, complete with it's own economy and different societies based on factors such as nationality, interests, and even sexual fetish.
PlayStation Home, on the other hand, is a purely commercial construct. While one of the services goals is fundamentally the same ? to provide a place for PlayStation 3 owners to make friends and socialize ? the aspects of Second Life that make it a true virtual world aren't present. You have no economy to speak of, with new items and customization options coming at a cost from Sony and its partners. While the addition of Clubs and Clubhouses does add to the social aspects of the service, the program's architecture really doesn't allow for communities on the same scale as in SL.
