Sticky vs Announcement

This may have been true before, but it's much more obvious now; Announcements get their own block with borders, while Sticky threads just sit at the top of the other threads.

I think some of the header threads that we've made Sticky should be changed to Announcement to set them apart. Use Sticky for threads that are important for a while, but would be un-Stuck when no longer current.

I'm going to mess with it in the Bass forum.