In tracking all the issues being reported, I'd say 75% of the problems that people are reporting are the result of using task killers, which are no longer supported by Froyo, since Froyo eliminated the ability of these apps to kill processes. It's a shame there isn't a way for Froyo to block these incompatible apps from being installed in the first place.
The second thing that resolves most issues, is a hard reset. It sounds like - for whatever reason - a simple upgrade to Froyo isn't enough for many upgraders.
Once you remove those 2 things from the picture, you have about 6 issues that are HTC related, 6 that are caused by 3rd party not working properly with Froyo, 4 that appear to be Froyo related, and the other 2 being a result of people who used some type of ROM other than the OTA.
So, I think the path to success for those of using a Droid X, is to do a hard reset before we install Froyo, do another one after we install Froyo, and to not use any 3rd party task killers. When we go to install our 3rd party apps, we should probably check recent reviews/comments for each app and make sure there isn't a laundry list of people claiming it doesn't work or is causing problems with Froyo.
It also appears HTC's Sense overlay is a lot more complex than the widgets/blur stuff that Moto provides, so I'm thinking the impact for us will also be a lot lower.