Snake's English voice sounds like that mostly because Hideo Kojima based the character of Solid Snake on Snake Plisskin in the first place (apparantly, Mr. Kojima is a huge "Escape from New York" fan, even going so far as to have Snake "disguise" himself as a character names "Iriquois Plisskin" in MGS2)).
Granted, I do prefer Snake's much deeper Japanese voice, Akai Otsuka, but I understand why David Hayter did his voice the way he did.
My only complaint (with all the English versions of the MGS games, actually) is Liquid Snake's awful English voice...when I think uber-tough terrorist military leader, I DON'T think "Y'know, the guy that did Leonardo on the Ninja Turtles cartoon would be a perfect voice for him". The guy that did Goliath on Gargoyles would have better matched Liquid's Japanese voice, and fit the character better in general.
Overall, I'm loving Twin Snakes. I've wanted a MGS2 quality remake of the first game since I saw MGS2, and any fears I had about how the game would control with a Gamecube pad were laid to rest when I got my copy today (the X-Box version of MGS2 had awful, game-destroying controls, and I was worried that would happen here also).
Yes, I'm a huge Metal gear fan, can you tell? ^^;