Dozens of businesses went to the Google forums to complain that their Google Maps reviews are missing. But a couple of days later, the reviews are now back.
To some business owners, this can be really upsetting. For example, one said "Last week i had 25 reviews. 22 great and 3 bad. Where did they all go? It has taken 2 years to get them. Can i get them back?"
There are dozens more like this.
Mike Blumenthal explained in one Google Places Help thread that typically with Google Maps updates, such as the one from yesterday, the reviews go missing for a bit of time and them come back. Mike explained:
Reviews for some reason often seem to disappear when Google does some sort of upgrade to their system. One assumes that for some reason their indices get misaligned.You are not the only owner reporting this problem. There has been a recent upgrade and I assume that your reviews will likely return over time.
The issue is, Google is not good at communicating this to people. So we have dozens of threads with complaints.
Forum discussion at (didn't list all) Google Maps Help, Google Places Help & Google Webmaster Help.
