I found this when I was trying to figure out why I had so many keys and clicks on .NET Runtime Optimization Service.
I believe that it’s the exact same, as all subdomains redirect to the main site.
Side note:You’re not alone; a lot of other users also have a boatload of keys in .NET Runtime Optimization Service.
The beta site refers to the regular site during times that we are not actively beta testing. When we are, the sub domain is replaced with the new updates and it is locked to accounts flagged as beta testers.