If you've been anxiously awaiting Microsoft's Project xCloud game streaming service, you'll be able to test it out soon. Sign-ups have been live since September 24, and invitations are starting to roll out now. If you don't have one yet though, don't worry, as they're rolling out over the next few weeks.
Some users on Reddit are already getting the invitation. Others haven't received an email, but they're finding that they're able to use the service anyway. We weren't able to replicate this though.
When signing up for the preview, the form did ask what type of device you're using, and which company is your mobile carrier. It's unclear if any of these factor into how soon you'll receive an invitation to start using the service.
Games that you'll be able to start playing on the preview include Gears 5, Sea of Thieves, and Killer Instinct. If you want to sign up, you can do so here.