It's fairly easy to see who are the console gamers here and who are the handheld ones. Platformers this gen:
Little Big Planet (PS3)
Ratchet and Clank Future (PS3)
PixelJunk Eden (PS3)
Super Mario Galaxy (Wii)
Super Paper Mario (Wii)
Wario Land: Shake It (Wii)
de Blob (Wii)
Klonoa (Wii)
Sonic and the Secret Rings (Wii)
Super Monkey Ball Banana Blitz (Wii)
Cloning Clyde (360)
Banjo-Kazooie: Nuts and Bolts (360)
Sonic Unleashed (360/PS3/Wii)
N+ (360/PSP/DS)
Braid (360/PC)
Prince of Persia (360/PS3)
Megaman 9 (360/PS3/Wii)
Bionic Commando Rearmed (360/PS3/PC)
Prince of Persia Classic (PS3/360)
Mirror's Edge (PS3/360)
Super Mario 64 DS (DS)
Megaman Zx (DS)
Magaman ZX Advent (DS)
Drawn to Life (DS)
New Super Mario Bros. (DS)
Super Princess Peach (DS)
Yoshi's Island DS (DS)
Kirby Super Star Ultra (DS)
Kirby Squeak Squad (DS)
The Legendary Starfy (DS)
Rayman DS (DS)
Sonic Rush (DS)
Sonic Rush Adventure (DS)
Yoshi's Touch and Go (DS)
Kirby's Canvas Curse (DS)
DK Jungle Climber (DS)
Henry Hatsworth in the Puzzling Adventure (DS)
Chronos Twin (DS)
Ratchet and Clank: Size Matters (PSP)
Ultimate Ghosts N Goblins (PSP)
Megaman Powered Up (PSP)
Castlevania: The Dracula X Chronicles (PSP)
Megaman Maverick Hunter X (PSP)
Daxter (PSP)
Secret Agent Clank (PSP)
Hammerin' Hero (PSP)
Ape Escape: On the Loose (PSP)
My personal top five:
1. Braid
2. N+
3. Prince of Persia
4. New Super Mario Bros.
5. Chronos Twin