I think it was smart to release a Prologue. Combined with other even more highly anticipated games for PS2 gamers, like GTA IV and MGS4 for the short run there are more than enough reasons for many PS2 gamers to jump onto the PS3 bandwagon, so the PS3 can gain enormous momentum until the crucial holiday season.
GTP previews well what the PS3 can achieve in 1080p / 60 FPS (solid 30 FPS for replays) and MGS4 at 1080p / 60 FPS (solid 30 FPS for hectic scenes) will likely kill 360 vs PS3 hardware discussions. Sure a few other games like Uncharted (best graphics, no in-game loading), Ratchet & Clank: Tools of Destruction (smooth 60 FPS, lots of stuff going on) and Super Stardust HD (1080p, 60 FPS, lots of stuff going on) should already have accomplished this, but they aren't spotlight titles like Gran Turismo and Metal Gear Solid.
People can start saving up for christmas as they feel more confident games like Killzone 2, Resistance 2 and Motorstorm 2 will live up to their rumoured technical prowess like the end of the format war has effectively killed Blu-Ray FUD.