First the (minor) bug:
When you hit the link to "view more results in Bing" from a c9 search it searches [search term] site:beta.channel9.msdn.com.
Beta should, presumably, no longer be there.
I was trying to find something I posted ages and ages ago in a thread I started (at least I think I started the thread afaik); the search (neither C9, Bing nor Google) could find what I was looking for (I'm sure it's there though) and the only way for me to manually find it is to go through 200 odd pages of posts I've made to the forums over the years - it would be nice to be able to access a list of threads started (or even threads posted in, but not each post) without having to wade through every post made. Also it would perhaps be nice to get this list on one page only for easy searching using your browser's FAYT feature (I, at least, often find this a useful complement to/replacement of machine searching).