Facebook and Ray-Ban are cooking something up  - a good long while after having announced that they were working together on smart glasses. Now Ray-Ban has confirmed that it has something to announce on 9 September.

The tease is fairly enigmatic, but Facebook's activity in the last couple of months can fill out the gaps for us pretty capably, in particular the fact that Mark Zuckerberg and Andrew Bosworth have been uploading point-of-view videos of their outdoorsy lives in the last few weeks.

These suggest pretty concretely that Facebook and Ray-Ban have some sort of smart glasses to debut, and you'd assume they're in the shape of some of Ray-Ban's famous frames, for the partnership to have much value at all.

Based on what Facebook has been saying to investors over the last couple of years, there's almost no chance that these are augmented-reality glasses - that tech is still too far away from being commercially viable. From the teaser videos, though, we'd say it's safe to assume they've got the ability to record video.

The good news is that we won't have to wait long to find out, with the reveal date imminent and Ray-Ban making it sound like it'll be an actual release date rather than just an unveiling. That should clarify just how ambitious Facebook is being with this new project.

For now, you can sign up on Ray-Ban's website to find out more as soon as everything's made clearer tomorrow, so be sure to do that if you're particularly interested.