Read about it here:
PlayStation.Blog PlayStation Home Open Beta Launches Tomorrow
I got invited to the closed beta right before Thanksgiving and it's pretty nice. There have been some annoying things like kids who have a headset blaring their music and the pervs who flock to the girl avatars trying to hit on them, but other than that it's a good addition to the PS universe. The mini-games like bowling and billiards are fun...when you can actually get on them.