Alright, some people seem to think that sharing games on psn is illegal. Hell i thought it was illegal at some point but the truth is, its not.

Sony locks the games they don't want shared like Warhawk, GT5 e.t.c. and it appears after the 2.4 update, those locks have been removed so you can now game share warhawk and GT5. Before if you tried to play those games on a different account than the one that purchased the game it wouldn't let you but now you can.

Yes i know it FEELS dirty but its not. In fact Sony encourages you to share games

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That was just before PS3 launched. Facts in bold

Sony also plans to offer a wide variety of small downloadable games through a digital delivery service called PlayStation Store. At the Gamers' Day event, there were long lines in front of the playable version of flOw, a slow-paced action title with mellow music and surreal graphics, based on a popular free web game.
Many of the event's attendees noticed that Sony's other downloadable offerings seemed designed to mimic the games on Microsoft's service. Sony's shooter, Blast Factor, bore more than a passing resemblance to Geometry Wars, the best-selling title on Xbox Live. (Senseless PS3 hating[])

Sony announced that players who download games from PlayStation's online shop can share them on up to five other PS3 machines.
If a player logs into his PlayStation 3 account on a friend's system, he can download any game he has already purchased. "You can send that content to four other friends for that initial investment," said Tretton. "We want to get the game in as many hands as possible."
"It's not about generating profits at each and every interaction with the consumer," he said. "I think that really offsets the argument that says, 'Wow, that's a really pricey system.

so they do want gamesharing

lets gameshare ps3 home