There are many complaints in the Google Places Forums from business owners who aren't seeing their business listings in Google Maps appear correctly.
Some are reporting duplicate listings, some are reporting missing listings, some are reporting their Google Places analytics going blank and so on. Mike covered many of the issues being reported late Wednesday but it appears some of the issues still are a problem.
On Wednesday, Cecelia from Google said in a Google Places Help thread, "We're aware some of the business listings were not appearing on Google Maps earlier today. This was a technical issue that's now been resolved." But it was not resolved.
On Thursday, Cecelia responded to more complaints:
We're aware that this issue may not have been fixed for all users. We're still working to resolve this technical error as soon as possible.
I believe the issue is still not fully resolved, but Google is aware of them.
Forum discussion at Google Places Help.