I'm in the same boat. I purchased the Verizon branded 'Otterbox' holster from Verizon when I got my phone (paying way too much I should mention), and the required case + rubberized backing added way too much bulk to the phone - litterally a good 1/2" or more to the height, width and depth - each. This causes the phone to be obscenely large plus cuts off access to the side connections which I plan to use with the docking station once released.
I don't understand it - I can find at least a dozen companies making holsters for this phone with all of them requiring the shell. Granted the phone is new but it's been out in Europe for over a month.