Well, I replaced glass/touch screen successfully. I was actually able to save gaskets (in about 80% condition, but all in one piece) by using a hairdryer to heat up and loosen and a razor blade. Took me over 2hrs total...
There are 2 gaskets. A dust gasket that goes on screen, and an adhesive gasket that goes on faceplate to hold screen (screen actually ends up going in from front after detatching connectors).
Note that you need to separate back housing from mother board to disconnect cables and there is 2 sided tape holding together. Again, heating with hairdryer helps pull that apart without breaking anything.
If I were to do it again, I would buy new front housing which has screen adhesive tape installed + screen dust gasket + glass (parts would be about $120 before shipping)
Cellular Dr is expensive, but they have everything:
http://www.cellulardr.com/verizon-droid-bionic-faceplate-with-front-sensor-key-light-guide-flex-cable-and-touchscreen-lens-adhesive-android-motorola-xt875.html
http://www.cellulardr.com/verizon-droid-bionic-lcd-screen-dust-gasket-android-motorola-xt875-display-gasket-for-dust-prevention.html
You can buy glass.touchscreen elsewhere much cheaper, here is where I got mine overnighted:
http://www.dealsishop.com/motorola-bionic-replacement-screen-digitizer.html
I've read that Motorola will replace for $110, don't know if true. However, that voids warranty (you "dropped" it) and you'll be w/out phone for a while.
Best of luck to all do-it-yourselfers!
-Steve