The physical home keys is the only thing I don't like about my DX so far. They're just something to break or get loose. I would have preferred if they were like the ones on my Droid 1.
I didn't like the physical Home keys at first, but I like them now. No accidental button presses now, as mentioned earlier, but most of all, I like the fact that the Home button can be used to wake up the X instead of the Power/Standby key at the top. Much easier to get to with one hand.
Supposedly the design changes to the keypad and physical keys for the d2 came from user feedback on the d1. Just something I read on phonescoop when reviewing before I got my first droid
Big fan of the physical keys. I am coming from a BB Storm... touch to feel first, and then press. I just wish I could use the physical keys to illuminate the screen to see notifications (old blackberry habit).
My wife has the Incredible and I feel like I hit the wrong key occasionally.
I like not having to hit the power button at the top of the 4.3" screen, just hitting the home button right there. I think the screen size may have been a factor, seeing as it does take more effort to hit the DX power button than the D2. It also feels like my iPod Touch. Say what you will, it had a very intuitive unlock pattern, which is very similar to what the DX has achieved with the physical buttons.