Users have to provide Microsoft with names for preview invites, but like was posted, they're nearing their capacity and will be sending out fewer program invites as a result.
Also, there is nothing scary about the preview software. I had maybe a couple of games crash in my months in the preview, but that crap happened on the general release software. It's highly stable, and you really can't even tell you're in the beta.
You can tell if you try and party with someone not in the beta. I don't know if they've fixed that, but it used to be an issue. They wouldn't allow parties between beta and nonbeta users.
You can tell if you try and party with someone not in the beta. I don't know if they've fixed that, but it used to be an issue. They wouldn't allow parties between beta and nonbeta users.