It has been an evolution to watch how Google handles results for locally-based searches. The challenges for getting a site optimized for a local search were already significant, but it has now taken on greater importance.
If you do a search for “columbus florist” (and if Google assumes you mean Columbus, OH), you can now see the local listings appearing as if they are organic listings. The only thing that differentiates them from organic listings is the Places info (image, address, phone number and map icon) that appear underneath the listing. These are Google listings on steroids!
It used to be that if you could get on to the first page of organic listings (around fifth to eighth position) where you would share the space with a list of ten very compact local listings, you could see some improvement in your traffic. Now, with this new layout, the local listings take up an enormous amount of real estate, while only four of the original organic listings make it onto the page. If you are in fifth to eighth position, you can forget about it.
This will dramatically increase the importance of optimization for Google Places. It also seems to give more strength to content-heavy sites like directories where there are local results.