Yeah, I've never heard of those games until couple weeks ago. And when I saw trailers/play movies, they are worth buying PS3 for.
You probably never heard of them because they're Sony's first party games or exclusives (Heavenly Sword was abandoned by Microsoft, I'd have considered buying 360 instead if they didn't)
The games I listed are either already out in Japan (Folklore aka Folks soul) due out in Q3 (NGS, Lair, HeavenlyS, WarHawk) or Q4 (GTA, Bladestorm, Uncharted)
It hasn't been even a year since PS3 came out, and the first party programmers are doing a good job (finally good use of Sixaxis controller)
I don't mind grabbing NGSigma even though it's an old game port because Rachel is playable
(I bet there is still plenty of empty space in that blu-ray though. They could have done more..)
I already own NDSL, PSP my girlfriend has NDSL, Wii (and GameCube)
I don't care if game companies leave Sony, as long as their game isn't totally cancelled. I can easily get and mod 360, which isn't too expensive anyway.
I'm not a big fan of FPS/fighting games (unless FPS supports USB mouse) So even if Tekken, DOA, VF, SC came out PS3 exclusive I wouldn't play it. Never liked MGS and BioHazard series either. Also sneak/assasinate games aren't my type either. (Assassin's Creed is awesome except the main guy isn't Prince of Persia and will die in one hit)
As I said so many times, even if I already owned a 360 I'd get PS3 because it's the best priced blu-ray player and will be the only addition needed on my home theatre for a while. The gaming features come as extra for free.