If I had to guess I'd say the game will either work exactly the same on PS3 or it will behave differently in a buggy sort of way. I guess its possible that things will be improved but I doubt it.

They haven't really said yet how they are achieving the PS2 backwards compatibility so its tough to say. Unless I just missed the announcement.

PS2 had the PSX processor built in (it was the IO processor for PS2 games). I would guess they have a miniature PS2 processor inside the PS3, (probably a chipset similar to PSP to cutdown on the overall development cost of PSP + PS3). If that's the case it'll probably play almost identical on there. Theoretically though, they could always boost the resolution of PS2 and PSX 3D games on the PS3 though. But that wouldn't really apply to MAT2.

I have heard talk about them rereleasing it altogether. How dreadful.

You mean we have to buy it again. What has the world come to? Talk about robbing us, we've been loyal gamers, why would they do that to us? I guess they like screwing us.

If they rereleased MAT2 for PS3 and the likes adding UMK3 and giving all the games netplay, it would be worth buying it again.