Just for information, this week's Hokanko Famitsu article reports what Vita games in top 30 did, approximately, according to Enterbrain
[PSV] Hot Shots Golf 6 (SCE) - 52.000
[PSV] Uncharted: Golden Abyss (SCE) - 43.000
[PSV] Dynasty Warriors Next (Koei Tecmo) - 32.000
[PSV] Lord of Apocalypse (Square-Enix) - 29.000
[PSV] Disgaea 3: Returns (Nippon Ichi Software) - 22.000
[PSV] DLC Racer (Bandai Namco) - 19.000
And since GameDataMuseum updated some of the 3DS titles
3DS Top 15
[3DS] Mario Kart 7 (Nintendo) - 451.932 / 1.082.391 / 41,75% 01/12/11
[3DS] Super Mario 3D Land (Nintendo) - 344.698 / 1.042.511 / 33,06% 03/11/11
[3DS] The Legend of Zelda: Ocarina of Time 3D (Nintendo) - 182.998 / 481.812 / 37,98% 16/06/11
[3DS] Monster Hunter 3G (Capcom) - 471.055 / 471.055 / 100,00% 10/12/11
[3DS] Nintendogs+cats (Nintendo) - 68.973 / 389.028 / 17,73% 26/02/11
[3DS] Professor Layton and the Mask of Miracles (Level 5) - 117.589 / 345.511 / 34,03% 26/02/11
[3DS] Pokemon Rumble Blast (Nintendo) - 91.613 / 231.829 / 39,52% 11/08/11
[3DS] One Piece: Unlimited Cruise SP (Bandai Namco) - 76.578 / 198.714 / 38,54% 26/05/11
[3DS] Samurai Warriors: Chronicles (Koei Tecmo) - 43.044 / 146.334 / 29,41% 26/02/11
[3DS] Super Street Fighter 3D Edition (Capcom) - 38.557 / 135.925 / 28,37% 26/02/11
[3DS] Resident Evil: The Mercenaries 3D (Capcom) - 61.306 / 118.117 / 51,90% 02/06/11
[3DS] Tales of the Abyss (Bandai Namco) - 68.218 / 114.439 / 59,61% 30/06/11
[3DS] Ridge Racer 3D (Bandai Namco) - 34.663 / 110.415 / 31,39% 26/02/11
[3DS] Winning Eleven 3DSoccer (Konami) - 26.222 / 107.274 / 24,44% 26/02/11
[3DS] Pilotwings: Resort (Nintendo) - 27.729 / 83.926 / 33,04% 14/04/11
Note: some of these titles are updated at an older date, and for the newly updated it isn't clear the week the update refers to.