I tried the exploid exploit to root my Droid 2 today and it's a no go. The exploit was patched with Froyo as will it be patched with the Droid X Froyo. So when we get Froyo on Droid X we will most likely lose root, unless of course we get it on the Droid 2 and it applies to the Droid X as well.
It was birdman who came up with the exploit, but he would (or someone who knows enough) have to modify some files, and then do the same thing as the X. The same exploit rooted the i1 and the devour. It's an exploit in motorola android phones, but it is patchable.