Just received the new redesigned Casemate Tough case! It now fits the sides better and the volume rockers and power buttons can be depressed easily now.
I tried it with the extended battery but the lower part of the hard case doesn't sit so well due to the extra thickness and I can feel the case flexing slightly when I grip the lower part. It also left about half a millimetre gap between the edge of the soft case and the edge of the hard case near the bottom connector area.
But if I take out the extended battery cover, the Tough case will fit nicely. However the Tough case has another problem which is that the aperture for the rear camera + flash is slightly bigger than the standard size. It seems some of the earlier cases had this issue as well. So if I were to use the case by removing the battery cover, there is a gap between the camera unit and the case which will potentially allow dust to enter the inside of the phone easily.
The CaseMate Tough case is a solid case which will fit the Original Galaxy Nexus with the standard battery pack nicely. The best fitting case I have for the extended battery pack is the SGP Ultra Capsule still.