I spent a good bit of time playing around with the Incredible today in a Verizon store, here are some of my first thoughts:
The changed soft buttons took me literally two minutes to adjust to. No problem at all. SenseUI is a nice change, but aesthetically, my Droid has been running a Sense-esque dark bar for ages now.
The Incredible screen looks very bright, though I feel like pixelation is slightly more evident on the Incredible than Droid. This may be caused solely by lower brightness settings on my Droid though. I didn't take enough time to compare this aspect.
One annoyance with the Incredible is that it doesn't lay flat. It has this wonderful coating that would keep it from sliding around on hard surfaces, but the camera lens protrudes from the top of the phone. I am quite confident that the Incredible would slide around on a car dash. In simple push tests, the Incredible slid startlingly more than the Droid.
The Incredible feels great in the hand. It is plasticky, but this didn't bother me much at all. The black paint of the Droid chips quite a bit, and I suspect that the Incredible's black plastic will be less susceptible to this.
As we all know, the Incredible is extremely fast. I was impressed, and I expected a lot. For reference, my Droid is rooted and variously clocked between 800mhz and 1.2ghz. The Incredible blows my Droid away in usability. All camera functions are completely smooth, everything is completely smooth. Bravo HTC.
Speaking of the camera, it's photos were fantastic. And quick.
I'm still debating whether or not to make the switch. I'll almost certainly end up getting it one way or the other. The biggest problem for me is the lack of free wireless tether (root), but hopefully this will be rectified in the near future.