I've been tracking Google's local search experience for a while (I work in Bing's competing local search product). Since February 2012, I've noticed only three variants or changes to the way in which local search results are presented on the main search page. The first is the number of ads displayed with each search. The second is the size of the map accompanying the search on the right hand side. The third is the prominance of the micro-poi (the small dots on the map) in the map design (they are now faded a little to help make the main information stand out).
So, in summary, there is not much happening on that surface - the main Google search results page.
Local search interactions tend to happen in one of two ways. The old-school approach is via a pair of text boxes. The first captures the what (restaurant, bar, sushi) and the second captures the where (Redmond).
This was the UI used in 2004 with the original Google product.
Over on Google+, I'm seeing quite a lot of energy being put into the local experience. While there are many Facebook like aspects to the experience (but less of the Facebook UI clutter), it is interesting to note that the query interface has cycled back to the two box approach.
Overall, my guess is that Google is focussing heavily on iterating their experiences on the G+ platform while the SERP (the main search results page) is largely cruising along with few changes.