3.1, but the claim to fame for the 8.9 Tab is that it is the world's thinnest tablet and one of the lightest at just 470g. It clocks in at a svelte 8.6mm, which makes the iPad 2 look like it still has its baby fat (at 8.8mm).
It has been rumored that the Galaxy Tab 8.9 would have a June release date, so this FCC news looks like a confirmation of that release window. Although, as of right now, this release only applies to the WiFi-only version of the Tab, not any 3G/4G variants. The WiFi Glaxy Tab 8.9 is expected to retail for $469.
source: Android Authority