With the new SAE J2807 standard the Tundra Crewmax tow rating for 2012 dropped to 9k. IMHO the standard is still flawed as it really only measures power to pull. All the current half tons on the market have plenty of power to pull 10+k but few have the payload to carry the tongue weight it would have. Pretty much all the 1/2 ton trucks will far exceed several other ratings before coming anywhere near the magical tow rating.
From experience, you should be able to tow that tt with ease but proper balance and hitch setup is key.