google maps and pub reviews

I've been having a long look at Google maps on my phone this morning and found that pub locations can be turned on. It is out of date and some inclusions are a bit dubious, but people are adding reviews. Other sites such as this one and qype are referenced and I found some of my more recent from PUG included. I was wondering if anyone knows how this is done. Are people employed to trawl the net looking for reviews or is it automatic using such things as daddylonglegsbots.