The concept of Ruin is pretty straight forward. Each player has a dungeon/lair. The object is to run around and enter other players' lairs/dungeons and try to defeat them, all the while, defending your own. It looks very much tower defense and Torchlight all rolled into one. Ruin comes with a PlayStation 3 addition that players can continue exactly where they left off on the PS Vita. No need to worry about playing in line at the DMV and then going home to continue conquering someone's lair, while pwning face. Ruin is really aimed to be online all the time, so it will be interesting to see how this game pans out across platforms. Game play is in real time, so while you're off killing baddies in your buddy's dungeon, you could also be getting attacked at the same time. A cool little twist on the action RPG style of game play.
It was funny, because during the press conference Travis Williams, Senior Producer for SCEA, accidentally said "PC" which makes me assume there are bigger plans for Ruin. I can only hope, because we need more Action RPG's in the Steam community, and anything tied with PS3 is okay by me!