Good to see I found this post. I have been surfing this forum and another Android forum since I made the switch from my 3GS to the Incredible. But last night, I hooked my phone up to the a cheap wall charger from MonoPrice. I believe someone linked it in this forum or the other. Anyways, as it was plugged in, I was going to make sure my alarms were set. However, I could not operate the screen (as posted the op posted on this forum). LoL, I was actually cussing my fingers for not working. But then I got out of bed and kept trying it. Nothing. Unplugged the phone, it was all fine. Plugged it back in, nothing. So I tried the HTC charger, and it worked fine. I tried 3 of my apple iphone/ipad wall chargers, all worked fine. The screen worked with each of them. However, the cheap one from MonoPrice did not let me use my touchscreen. I tried the cheap MonoPrice car charger. It worked fine.
Going back to the OP, I tried my car dock (old one from my iphone that is suctioned to the windshield), no problems at all. However, when I toss the Incredible on the couch, it does not work 50% of the time. I tried this with my dad's Incredible. Same, 50% of the time it will work or not work. Styrofoam? It worked on the styrofoam.
One thing my dad's phone and my phone has in common is the high gloss
case. It was hard to tell, but did you have a case on yours?