There are dozens of threads at the Google Places and Maps forums with complaints that their business listings within Google Places have been suddenly changes to "Pending" status, from the "Active" status.
A Google Places Help thread has confirmation from Google that this is indeed a bug. Google Places representative, Brianna, confirmed last night that the issue is a bug in the Google Places system and Google is working on fixing it. Brianna said:
Thanks for reporting this issue. We are aware that listings have reverted to pending in users' accounts. To check if your listing is live, please do a search in Google Maps for [BUSINESS NAME in POSTAL CODE].
Boost ads are unaffected by this issue.
We will follow up with more information when we have it.
Personally, I do not seem to be affected by this bug - but many many businesses and local SEOs are reporting this issue.
There is no estimated time for a fix.
Forum discussion at Google Places Help.
Update: Jay from Google posted an update that this should be resolved.