Are we talking about HD re-releases? Like the Ico and Shadow of the Colossus, Resident Evil, Silent Hill and Metal Gear solid "HD" collections coming out? Or do you mean legit remakes more like Halo: Anniversary coming out and the old Resident Evil remake for Gamecube? The Latter is cool, the former is honestly kind of lame. I love Silent Hill 2 and 3, but as many people have said in the past, the games are just as high in quality on the PC as they will ever be. Resident Evil HD collections just seem like a rip off. Resident Evil 4 is only 5 years old and has been released on everything under the sun except Xbox consoles and the PS3, so maybe for 360 owners its a good deal. The Code Veronica game is a bit dumb. I honestly prefer RE4 to Code Veronica as RE4 didn't really need a graphics uphaul... But Code Veronica had Dreamcast graphics. Putting it in "HD" really just makes it easier to see how ugly it looks. The Team Ico HD collection is a cool deal, but as with the RE games it feels like Sony's just taking us for more money like they have with the Prince of Persia HD Collection, Sly Cooper, God of War, etc... They could have just, you know, left in backwards compatibility and essentially accomplished the same thing. I'm picking it up because I have never played the games before (I know, I'm already ashamed) but if PS3 was still Backwards compatible I probably would have just picked up the games by now and played them for less than the $40 this will cost me. Trophy support is a plus, but not a seller.
Now actually REMAKES with actually updated graphics and not "We made this game look less grainy" are a whole different story. Playing Halo: CE with Reach's graphic engine is cool. Playing RE for the gamecube was awesome. THESE are the kind of re-releases I can get behind. There are some cases where HD re-releases is good, like the MGS one is good for 360 owners and those who don't on a PSP. The Silent Hill HD collection is good for 360 owners who want to play SH3 on the 360. I have more of a problem with HD collections like God of War and Team Ico where it really just feels like they're gutting us for money, as all those games are playable on PS2 and if they just kept in backwards compatibility it wouldn't have been an issue. At least in the Halo Remake's case it's completely optional and you can still choose to pick up the original game and play it on your 360, and you don't feel like you're being forced to but the remake if you want to play Halo with better graphics.
All in all, it was a cool idea back when they remade games that looked bad in todays standards, its a lame cash in when they take a game and make it look "newer".