oh my god I LOVE TOP GEAR!! (sorry had to let it out)
I thought the stig was Tiff Needle as-well but would he be able to do 5th gear and be the stig at the same time? Plus he isn't THAT fast he's just really skillful.
Me and my mate were talking about this and he recons it's damon hill (mearly because he looks the same in his overalls (Y) )
But when you really think about it it could be anyone, there's loads of touring car drivers that could do it and loads of ex f1/indycart drivers etc.
If anyone knows for sure please post. :)