Mary Fons (the daughter) came & did a workshop at my quilt guild a few months ago. She is getting more into fabric designing now (
http://springscreative.com/maryfons/) and announced maybe a year ago that she would be less involved with the show -- I believe she still does something in the magazine each month, but I don't get the magazine so I'm not positive. Liz Porter (co-founder, friend of Marianne) left the show quite a while ago & Marianne Fons (the mom) retired but still made a number of appearances on the show with Mary because they liked working together. The two of them also launched a new podcast on iTunes
Quilt Your Heart Out.
Like Mary Fons, I don't own a TV so I'm not sure who is hosting these days -- but I believe they are guest hosts. I haven't heard that they've hired a permanent replacement or anything & I don't know whether the program will continue beyond this season.