Outrun Online Arcade, Castle Crashers, Limbo, Stacking, From Dust, Braid and PAC Man DX are also on PSN, and lots of the games on your list are also available on pc so not really XBLA exclusive.
There are so many good exclusives on PSN too: Super Stardust HD, Critter Crunch, Dyad (GOTY 2012 for me!), Fl0wer, Dead Nation, Echochrome, Fat Princess, Journey, Cubixx HD, Noby Noby Boy, Pain, Cubix, all Pixeljunk Games (PJ Shooter 1 + 2, PJ Sidescroller, PJ Eden etc...), Rainbow Moon, Soldner-X 1 + 2, Retro/Grade, Sideway New York, Blue Toad Murder Files, Savage Moon, Shatter, The Last Guy, The Unfinished Swan, Mutant Blob etc... But Sony really should do more promotion for those games (like Summer of arcade and House Party on XBLA) since lots of PS3-owners aren't even aware those games exist.
Here's a complete list of PSN games: