There's definitely something going on over the last few days with Google. I added Schema.org microdata reviews the beginning of last week and the stars all came up nicely a day later on all my landing pages.
5 days ago I changed the microdata types to more accurately reflect the content (eg. product to service, votes to reviews) and since then only 1 landing page had changed and some have lost their stars all together. The one that has changed is not showing some of the microadata (such as img) that the preview tool shows it should.
On top of this, these specific pages all seem to have messed up title tags - the cached version source codes are all correct and up-to-date but the SERPs seem to show title formats from months ago and malformed at that.
So I wonder whether they are trying to roll something back and coalesce data elements?! Just drop the index and start again on the whole web Google ;)
Maybe they have gone back to white-listing too given the delay in change I am seeing compared to before. Or perhaps only certainly categories are un-white-listed?!