Getting ready to upgrade to a verizon 4s in a few days, and I can't wait.  Been on a Droid X for about a year and have grown to hate it.
There's just too many problems with speed, functionality, etc.  I have loaded custom roms (cm7, Apex, etc) and even used stock (I clean the cache too), but the same stuff happens after a month or two - constant freezes, reboots, loss of service for no reason.  One of the most annoying things is when I try to call someone, it will call the last person I called instead...wtf?  Oh, and the battery life is beyond awful.
I'm not really bashing droids, just talking about my experience.  I'll miss the customization, but I'd rather have a phone that doesn't require me to flash custom roms for it to be decent.  It's been a rather negative one, so I'm taking my business elsewhere for this upgrade.  It certainly can't get much worse, and if it does, I have another upgrade next summer.