As noted several weeks ago, Google Groups for Maps was being moved to new Forum Platform. That switch has now taken place. From the Lat Long Blog:
The help forum is still an area for users to come together to discuss and share their knowledge of Google Maps and the Local Business Center – only now it has a new look. It’s integrated with our help center, which makes it even easier to jump into the forum while you’re browsing the help center. You can search for content across both the forum and help center articles as well.
The “help” link in the Local Business Center goes to the help center where they are offered a choice of going to the new Maps Help Forum. This integration and new layout should make the forum easier to find from the LBC.Google Groups for Maps Moved to new Forum Platform by Mike Blumenthal