For those of you (me) that aren't able to get a key to today's new beta build of A Hat in Time, here's footage of the 1st act of several levels in the beta.
If you're a Kickstarter backer and pledged enough for the beta, and haven't gotten a key yet, you may be out of luck til Monday. Official word from Gears for Breakfast.
Even if you didn't back the game on Kickstarter, or on their site, you can pay for the beta on Monday.
UPDATE: If you want to see more, several people are livestreaming their playthroughs/speedruns of the beta on Twitch. Just search for A Hat in Time.