Sure, it'll happen in some shape or form. They're far enough past their sell-by date and there's enough interest in the band that they'll release everything left/milk it for all it's worth.
How much money are we willing to spend on Throbbing Gristle Videos
Personally, none at all. There's enough of a record of their live performances enshrined on youtube. Watching Orridge gyrate was never much of a draw for me and the other three just stand around awkwardly. The interesting thing to me was always the music and how they generated it. I'm not holding my breath for any new groundbreaking material but it'd be nice to be surprised.