Android 3.1, but we're afraid the timing and features included in that update may depend on where you reside and which one you bought. For instance, while both Verizon 3G and WiFi-only Xooms in the United States are seeing the latest Honeycomb slowly trickle in right now, Motorola says that the WiFi version won't have movie rentals available immediately after the update. What's more, though the new hotness doesn't seem to bring microSD card support to US devices, Motorola says that Canadian models will get that exact functionality "soon." What if you don't live in North America at all? We're afraid we can't tell you.