Google is clearly "up to something" with Google Local reviews. You can no longer "see" a business's reviews in the "new" format of Google+. You can only see them on Google maps via a Google search result.
For potential reviewers, the new instructions to write a review on your business are to go FIRST to Google maps, find your company, and then write a review. So bye-bye Google+ for reviews.
For the official Google instructions on how to write a review, go here.