Yup, the seed is: "Toothpaste on my Teeth" without the quotation marks. This has been tested on 1.2.5 and 12w23b, so it should work on other snapshots too.
And now for diamond coordinates!
If you do try this seed out, and find diamonds not listed here, please post the coordinates.
There are also many other cool things, including a few surface level lava lakes somewhat near the spawn!
And thanks for reading!