I heard emails from Microsoft regarding a kinect beta were sent out last week. Is this a legit thing?

Short answer: Yes.

It should be, yes. Xbox Live's Major Nelson posted a bit more information about the beta program on his site here. In summary, as long as they're coming from the Microsoft Connect site and the sign ups take place on Microsoft Connect's site, the Kinect beta invites should be real.
 
It certainly wouldn't surprise me if a few questionable people tried taking advantage of the Kinect beta to steal personal information, though, so I'd always be cautious about this sort of thing if you actually get an e-mail.

Apparently, but like PsEG said, do watch out for scam attempts, they always appear around this sort of thing. But the actual beta is real, lord knows how they're gonna go about it, but it's a real thing.

As long as you don't give any personal information to them, it should be allright.

I dunno, are you a new user?

I would love to get in on the Kinect Beta. I am really unsure of Kinect. Getting in on the Beta and playing some Dance Central might change my mind. : )

I personally would like to get up on that. I bet my gf and I would have a lot of fun with it.

Sounds legit from everything I've read.  13 feet of clearance, if true, kills that thing.