In short, if your search contains anything that might signal local intent, Google may show a map above the AdWords ads on the right, and then automatically include some local results within the organic results. Plus, they added a "Places" link on the left hand navigation bar in Google's search results.
If you don't see it yet, then you can try it out by clicking here or looking at this screen shot:
Greg Sterling has a nice review at Search Engine Land. Greg said "the changes reflect Google’s commitment to local." It does and many local optimizers are really happy with this and can't wait to start messing around and seeing how they can get their local results top.
But AdWords advertisers are not too happy. The map in the top right position moves down their ads that would have shown up otherwise. They are not happy. Plus, they feel it is merging the organic results with the paid results by having an organic map above on the right, of the ads.