Unfortunately the Galaxy Tab 10.1 comes with a locked bootloader, creating a speed bump for hackers. Strangely, there are reports that some new Galaxy Tab 10.1 owners came unlocked.
So what will an unlocked bootloader give you? Well nothing really, unless you are a hacker and want to get some developing on. The folks at XDA will crack it soon enough and make it possible to unlock previously locked bootloaders.
So how do you check to see if your bootloader is locked? It could not be easier. Just power off your device and power it back on. If your Galaxy Tab has a lock image below where it says Galaxy Tab 10.1, then you are unlocked. See the image above for reference.
Source: Android Central