*UPDATE!*AMC has released a new official clean cut of the Walking Dead trailer shown at San Diego ComicCon, as well as the premiere's release date!
From AMC's blog:
AMC has announced that its newest original series, The Walking Dead, will premiere on Halloween night, Sun., Oct. 31 at 10PM | 9C. The Sunday night series will debut with a 90-minute premiere episode. Subsequent episodes will be one-hour long presentations.
old post: i don't know how long it'll be online, but here's a fan's handycam of The Walking Dead trailer from the panel at SDCC. Enjoy! http://www.youtube.com/watch?v=qBiI6YRfWIY
here's a slightly larger and clearer one, but it has a lot of background noise. http://youtu.be/yHN6goQTP9k