I share your sentiments, especially about David Hayter. I think TPP will be a good game, but from the reviews, it seems to bear very little semblance to the other games in the series. It's interesting to note, that Kojima was actually developing this as an IP called Project Ogre, before he made it into another MGS game. So, that may account for why it's so different in its execution.
"What has me concerned the most, is the limited voice work and sparse cinematic cut-scenes that were mentioned in the reviews. I love gameplay, but MGS has always been a story-based experience, with enormous dialogues and set-pieces to go along with them. The lack of codec conversations is also pretty jarring, as they were some of the most fun things in MGS 1 to 4."
I am glad I am not the only who feels this way. I agree that the epic set-pieces, dialogue, cinematic cut-scenes, and David Hayter is Metal Gear Solid. That is not to say you can't make a game without them but I don't think its Metal Gear Solid IMHO. I feel like many of us are here for those very reasons, they all stick out in our memory as those great moments of gaming. I feel that this game is going to focus too much on an action movie experience while highlighting how terrible of a person Big Boss becomes. I will miss those epic/memorable boss battles and tragic monologues from characters. Kojima was the one who insisted on the long cut-scenes because of his love for Hollywood films. It seems to me that this Metal Gear Solid was made for a general audience rather that MGS fans.
One can of worms that I have to open is who do you think suffered more/had a harder life Solid Snake or Big Boss? My vote Solid Snake, I will defend my opinion later.