If a person manually updated to 2.2 will you still receive the Verizon OTA 2.2 update? Is there any difference between the two?
I don't really think you risk anything by manually updating as it's the same file. Not to mention it's almost impossible to brick a Droid with the software available and assuming you can read directions. With that said, the updates should be finished by the 18th so there really isn't a need to update manually unless you really don't want to wait or think verizon is going to give everyone the run around again.
It is the same build, and the files can be pulled directly from Googles servers.
I dont think you will get the update, but future updates have been said to go through since it is a signed build.
This site gives a step-by-step guide.
This is still at your own risk. A friend of mine could not wait even though they live in the same area, and it went just fine.
http://www.examiner.com/x-8134-SF-Gadgets-Examiner~y2010m8d6-Motorola-Droid-Android-22-OTA-update-delayed-indefinitely