Finally, on the contrary to what I posted some days ago, Microsoft announced yesterday that there will be a public VS 2010 Release Candidate, and that “the planned final launch date is moved back a few weeks”.

This is good news for developers of add-ins, because:

1) That release will be the first one where the automation model of the WPF-based commandbars will work without the many critical bugs of Beta 2.

2) Developers will be able to release add-ins compatible with VS 2010 RC for the end users to test them.

That said, there will be minor bugs that finally won’t be fixed
even in RTM because the bar to get them fixed is very high already today, but I
think there will be workarounds. I will post about them when the RC is released.