Don't have a 360, personally, but I've heard lots of love for both Bastion and Fez (think they're both exclusive to XBLA).
On the PS3, Journey, & Flower are both pretty cool (& by the same company).
I also liked Costume Quest & Stacking on the PS3 (...but those 2 may well be available on both consoles).
Vandal Hearts: Flames of Judgement was (imo) pretty "meh" as was Faery: Legends of Avalon.
2 games that I've bought & downloaded but haven't got around to yet (that both look pretty good) are the 1st Record of Agarest War game (which also has a "disc" version on the 360...on PSN, it was download-only) and Wizardry: Labyrinth of Lost Souls (which would only be enjoyable to those of you who like older-school style dungeon-crawlers).
Keep in mind that I'm probably missing a ton of the non-rpg ones since they're pretty much all I play...