I am by no means an expert on it....but I think she was "let go" due to cutbacks on the show. I miss seeing her there too, as its always fun to see a girl who can fab, especially when she seems cool, down to earth, and not particularly hard on the eyes either.
It was fun to see her on Mythbusters. So much so, that I was hoping that she would get a full time gig there. I'd take her over that Kerri chick any day.
Add another vote to have her come back and do some reunion episodes. Ian, you are pretty slick with a bender and welder, but bring back someone who cares less about their hair and bring her back

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