Great I hear you say: but what's ZBB and what does it mean for the product?

Well ZBB means Zero-Bug-Bounce that means that the compiler team have managed to drive the total number of active compiler bugs to zero. This doesn't mean that we are done but it does mean that we have gotten rid of all the old bugs that have been hanging around for a while and now all we have to deal with is the incoming bugs. It also means that our bug triage bar has been raised again so we are now looking at each incoming bug with a more cirtical eye. For each bug we now ask is this a bug that we really need to fix in the product before we ship - for many of the bugs we see the answer is still yes (especially if it is a bug reported by a customer - so keep them coming in) but for other bugs which do not, in our opinion, have a serious impact on the product we will postpone them until the next release. So while ZBB isn't the end of the Whidbey development cycle it is definitely the beginning of the end.