I have The Incredible, Droid 2(I just traded my R2D2 for a regular D2) and a Droid X. While I tend to use my X most, as it is the newest, my Incredible is by far the best device of the three. To me, Sense is a little more "in your face" compared to Blur. I'm not saying that's a bad thing as I actually think Sense is awesome, I just think it is more noticeable than Blur is on Moto's. That said, as far as performance goes, you cannot even tell Sense is on the phone. The Incredible is extremely "snappy" and responsive out of the box. I cannot say the same for Moto devices.
Not sure what your intentions are, but I need my devices to be rooted, and have the option to install custom ROMs. While I have been successful in that with all three devices, it is much easier to achieve on the Incredible. And much easier to use once you have it(hacking/romming).
The Incredible takes great great pictures. Megapixel shmegapixle. It don't really mean much unless you plan on blowing your pictures up. Even tho the DInc has an 8MP and the D2 has a 5, you wouldn't be able to tell the difference on a computer if the hardware and software was exactly the same. However, in my experience, the pictures on my Incredible come out looking nicer in a more consistent manner.
I do not hate my D2, but I will say that I am glad I have it as a "complimentary device". It is a cool phone, and by now means bad at all, but if I could only have 1 phone of these three, I wouldn't pick the D2. Now maybe I could talk myself into the X, but I'm pretty sure it would be the Incredible because I know it will run better than great and I will have more possibilites as well.
Also, Motorola is dumb putting all these stupid locks and restrictions on their devices. I kinda like HTC better as far as "user friendly" goes. So yea, I definitely think the Incredible blows the D2 out of the water as far as performance. IMO, if you take the carrier and OEM into account along with hardware, software, and capabilities, the Incredible is the best device on the market. I don't think you would be disappointed. Either way, fun can be had with either, so I hope you are happy with whatever you decide!
Lastly, if a hardware keyboard is important to you, lemme say this: I used to only like phone with physical keyboards. Then I got the Incredible(pretty much the first touch screen board I used over an extended period of time) and I was pretty surprise at how easily it was. Previously I had used my Mom's BB Storm, and hated touch keyboards lol. But after using the Incredible for a short while, I saw that they could be really good too! When I got my D2 I admit it made me realize that I had missed a physical keyboard, but during my time away I didn't even notice it. Now I am fine with either, it's not a deal breaker. OK I have gone on too long. Back to hacking meh phonez.
*EDIT* I just wanted to say again, the Incredible is extremely responsive! With CyanogenMod, SkyRaider, or stock, it didn't matter. It is a really fast phone. I love it
But really....it is. Fastest I've used.