The local office's theory is that I had a power "blip" and it caused my channels to change.... They hadn't heard of anyone else having the issues.
I wanted the Tivo mini anyway, and was able to get them to waive the $50 install fee so I was happy. I still don't undertand why they don't have any digitalink boxes if they have digital stations. I guess they don't want to give the free boxes out if they don't have to.