The psp has so many more games than MGS and GTA.. I have both and never use my DS, the psp is just an amazing system with alot of un-used potential, but it looks like it finally will be used soon enough.
PSP at E3 -
Metal Gear Solid: Portable Ops
Grand Theft Auto: Vice City Stories
Coded Arms Contangion
Silent Hill Origins
SOCOM 2
Killzone: Liberation
Earthworm Jim
Tekken: Dark Resurrection
Monster Hunter Freedom
Motal Kombat: Deception Unchained
Ratchet and Clank: Size Matters
Ultimate Ghosts n Goblins
And not to mention all of these!
50 Cent: Bulletproof G Unit Edition
300: March to Glory
Ace Comat X: Skies of Deception
Ape Escape Academy 2
Arthur and the Minimoys
ATV Offroad Fury Pro
Battlezone
Blade Dancer: Lineage of Light
Bomberman
Bounty Hounds
Brooktown High: Senior Year
Capcom Collections Reloaded
Capcom Puzzle World
Charlie Brown's All-Stars
Crisis Core: Final Fantasy VII
Dave Mirra BMX Challenge
Dead Head Fred
Death Jr. -- Root of Evil
Def Jam Fight for NY: The Takeover
Disney/Pixar's Cars
Dungeon Explorer
Dungeon Siege: Throne of Agony
Dungeons & Dragons: Tactics
Dynasty Warriors: Vol. 2
Earache Extreme Metal Racing
Every Extend Extra
EyeToy: Play Portable
Family Guy
Field Commander
FIFA Soccer 06 G
Gangs of London
Ghost Rider
Gitaroo Man Lives!
Gradius Collection
Guilty Gear Judgment
Hard Rock Casino
Hellboy
Hot PXL
Hot Shots Golf for GPS
Jackass: The Game
Juiced: Eliminator
Justice League Heroes
LEGO Star Wars II: The Original Trilogy
Loco Roco
Lemmings
Lumines II
Madden NFL 07
Marvel Universe Trading Card Game
Marvel: Ultimate Alliance
Mercury Meltdown
Metal Slug Anthology
Miami Vice
Micro Machines V4
NASCAR 07
NBA '07
NBA Ballers: Rebound
NBA Live 06
NCAA Football 07
Online Chess Kingdoms
Open Season
Pac-Man World Rally
Pirates of the Caribbean: Dead Man's Chest
Power Stone Collection
Race Driver 2006
Rengoku 2
Rush
Sam Suede: Undercover Exposure
Snoopy vs. the Red Baron
Sonic Rivals
Spore
Star Trek: Tactical Assault
Steel Horizon
Super Monkey Ball Adventure
Superman Returns: The Videogame
TalkMan
Test Drive Unlimited
The Fast and the Furious
The Legend of Heroes II: Prophecy of the Moonlight Witch
Thrillville
Tiger Woods PGA Tour 06
Tomb Raider: Legend
Traxion
Valkyrie Profile: Lenneth
Winning Eleven: Pro Evolution Soccer 2007
Winx Club: Join the Club
World Championship Poker: Featuring Howard Lederer "All In"
World Pool Championship 2007
World Series of Poker: Tournament of Champions
World Tour Soccer 2
Worldwide Soccer Manager 2007
WTF
WWE SmackDown vs. RAW 2007
Xiaolin Showdown
Yu-Gi-Oh! GX
So, with all of those coming out, and games like Metal Gear Acid, Syphon Filter, Daxter, Exit, Lumines, and GTA:LCS already on the system, the PSP is expanding to huge proportions, with a vast range of game types, it's well worth the price of admission..