Ok, sorry, I have to admit I knew it was still up. Claiming it was taken down is a classic tactic for getting people to click through. You've been RickRoll'd. (I'm not proud of it.)
Speaking of influential, check out the extensive Wikipedia page on the meme. The RickRoll has showed up in the Macy's Thanksgiving parade (with Rick Astley in person), a video from Nancy Pelosi, and a tweet from the White House Twitter feed. It is fully part of the pop culture.
http://www.youtube.com/watch?v=oHg5SJYRHA0