You can!
i just did it with Pete's Motorola Root Tools. (http://www.psouza4.com/Bionic/) just clicked unroot my phone. and it worked, it left superuser app but i uninstalled it and you can't even tell it was on.
i just did it with Pete's Motorola Root Tools. (http://www.psouza4.com/Bionic/) just clicked unroot my phone. and it worked, it left superuser app but i uninstalled it and you can't even tell it was on.