Chris Lang, CEO of Key Web Data, has spotted a feature of Google+ that appears to reveal the upcoming business profiles in testing.
If you go to edit your Google profile and edit the employment section, you can go to where you can add an employer, and Google will suggests various business profiles for you. Lang posted the following video demonstrating the feature.
Lang's video description says:
"Here's how you can find Google + Business profiles in testing before release. Just go to your Google + profile, edit the profile, then cycle thru the alphabet in a employer field."
In a Google+ comment, he says, "Nice to see Google is not screwing around and hard at work on this business / brand profile testing."
You can't actually go the profiles themselves, but as Lang says, "Why else would they show up under employers? Same UI/thing when you add employers on Facebook. Try and search 'em, you can't find them, believe me, they are business profiles."
Ben Petro commented that this feature has actually been around for a while. Still, it hasn't received a whole lot of attention.
Hat tip to Brett Tabke: