If u keep the stock rom u should get the ota. U will probably lose root when it does but when that happened on my Droid 1 I just rooted it again. Not sure if there will be a delay in being able to root again or if we can root immediately, but I'm sure when it happens the forums will be buzzin
I would imagine that the community will come up with the update for rooted users pretty quick. Just don't accept the update until you check out the forums...
I would never accept an ota while rooted. You quite frankly don't know what will happen. You could loose root, possibly brick, it may just fail, or it could cause thermo-nuclear war!
There is really no need to anyway, you can have the update via a rooted version of a leaked file far before it even comes ota. If you really feel the need to take the ota, unroot before you do and hope you can root again afterwards...