re-posting from HOFO. AT YOUR OWN RISK!:

This is actually pretty simple and does not require any hacks whatsoever.

What you will get:
Unbranded phone without any Verizon customization
More memory, ~10MB more for me. The MMS package alone uses around 4MB.
No Verizon links, no EVDO, no bs.
You can still install the customizations later if you need any of them, I don’t.
More features. The phone application alone has like 4 new services to play with.
Wifi & phone can be used at the same time, no need to edit the registry.
Possibly obex and other crap Verizon took out.

Steps:

Hard reboot the phone. This is done by holding the two soft keys and pressing the reset button. Hit "Y" to continue.
Go through the screen calibration, zone and password screens. When you get to the "Complete" blue screen where it asks you to tap to start using the device, put the stylus on the reset button but don't press it. Tap on the screen. You will get a message saying that the OEM (Verizon) customizations will be installed on 3 seconds. Hit reset as soon as you see the message and you're all set. When the phone reboots you will have a fully functional and unbranded phone without all the garbage Verizon adds to it. Wifi/phone can be used at the same time, there are no longer any locks. Obex may work as well, I have no way to test it. Also, you get some extra menu items here and there. Works flawlessly.

If you do need some of the crap Verizon installs, open up the Extended ROM partition and install it by clicking on the cabs. Don't run the remove. cab.