Most notably it fixes bug 690154, which should help out protz in particular and test writers in general.
we need bug 696027
Created attachment 568894 [details] [diff] [review] patch Pushed to try, but tryserver seems to be having some issues, let's see.
The last push didn't go well at all. I just merged and pushed again.
This one did much better. http://hg.mozilla.org/comm-central/rev/336a01b5aa31