Since April, Google has been testing a local pack in the search results that auto-expands the map section when you hover your mouse cursor over it. This now seems to be live or rolling out fully.
I can replicate it myself and so can Mike Blumenthal, Robert Spinrad and others I asked privately.
Here is what it looks like:
I am not sure if I like it, I prefer to click an icon to expand it manually but hey, Google tested it for a while and decided to roll it out – so they must like how it is performing…