I've heard of this and people call it a bad digitizer(I think). When this happens they say they can swipe their finger over the lock buttons and feel it vibrate like it unlocked, but the screen stays black. I've seen one of our member, FURBEARINGMAMMAL, describe this. Maybe PM him, he's all over the place in this forum, and ask him. If its under a year old(and not rooted) its still under warranty. Bring to a VZW store and see what they say.
CJM is right. If it's less than a year old and rooted you'll need to get it back to stock before taking it in. If it's not rooted then just take it into a Verizon store -- or call support. They'll send you a CLN (certified like new) replacement. I'm currently on one and I have to say that, other than the USB port being surprisingly loose, it's tight as a snare drum. The digitizer is actually a little more responsive than my old one, too.
If it's slightly over a year old then contact Motorola. They might still have a warranty on it. If it's a release-day one you're probably out of luck, though. But jump on this ASAP. The sooner you get it fixed the sooner you look like a hero, and the longer you wait the closer the warranty expiration date comes.
Hello, I have a Droid R2D2. I have had it since februray. It has been fine up until today when I accidentally put it in a bag with dry mud inside. This made the sliding mechanism very hard to use. I very little water and windex on the back slider piece and slid it up and down. I then wiped all of the excess liquid from it. It worked like new up until an hour or two later when the screen started to flicker. I locked it then unlocked it and it still flickered. So I turned it off and turned It back on and I saw the moterola sign flicker then disappear. All of the buttons work, it still charges but I cant see a thing! Please help!