They already did sort of remake the original Silent Hill, with Silent Hill: Shattered Memories. Rather than go the straight remake route like they did with Metal Gear Solid: The Twin Snakes, though, they decided to do a complete reimagining of the story and gameplay. They took the basic thread of Harry Mason takes his daughter to a creepy town and gets lost in it, and went in completely new directions. So, needless to say, doesn't fit in with the 'canon' of the other games, but I thought it was still well worth checking out.
Good info sir, I actually didn't know this. I've been dismissing the post-Silent Hill 4 games without much thought, but maybe this is a pretty rude gesture. I'll have to take a closer look at Shattered Memories, should be interesting to see where they take it.