The Galaxy Tab Plus for T-Mobile has been spotted in the wild. Pegged as a successor to the original Galaxy Tab, it is running Android 3.2 with TouchWiz on top and should work on T-Mobile's HSPA+ network -- hence the 4G label on the back. From the photos, it looks thinner than the original Galaxy Tab but not as crazy-thin as the Samsung Galaxy Tab 7.7 we saw at IFA. In other words, it may be a cousin to the Tab 7.7 but it doesn't look like a US version of it.
It's difficult to know specs for sure, but the tablet has already been checked out by both the Wi-Fi Alliance (PDF link) and the Bluetooth SIG. The device profile for the Galaxy Tab Plus leaked last month and suggests that it will have a 1024 x 600 screen resolution, the same as the original Galaxy Tab. A Cortex-A9 processor of some sort and dual-band Wi-Fi may also be on board.
Unfortunately, further details like pricing and availability aren't known yet. You can find a few more images at the source link.