Check your inboxes - beta keys have been sent out! They will stay active at least until Monday (possibly longer).
Beta Signups are no longer available.
Due to a mistake made by our QA team, you will receive two emails. The first one is missing the key - just ignore it and open up the second one :)
Remember to report any bugs using the bug report form (link in the email) and to fill out the beta survey when you're done playing (link in the email).