Just saw this when I was checking my account earlier. Full text is;
Create a Google+ page
Creating a Google+ page brings you closer to your audience by letting you have real conversations with the right people, connecting you face to face, and making it easy for people to recommend you on Google search.
Also has a check box to tick to indicate whether or not "you've done this".
Fairly agressive cross-product marketing from Google there - haven't really seen anything like this before. An interesting move, but has an air of desperation about it.
Worth noting that although it's posted as a "recommendation" there's no information or suggestion that it would impact your Adsense account in any way.