I might be mistaken, and I don't think I've seen it posted yet (and if it was someone point where please ), but: I think the "ignore" feature for forums is in 1.1, meaning you can pick what forums don't show up in What's New? listing.
I just tried it and while I see new threads in the test forum it doesn't show up when looking for what's new.
I believe it is a bug and should be reported in appropriate forum. Possibly, on screen resize event, width of the notice wrapper markup is not recalculated.