Yeah, I checked both and even did a search for it in the All mail part.
Did you even read the OP?
Lol In all honesty I did, but I totally mis-read it. For some reason I read it as "Got beta registration confirmation but not sure why I haven't received an invite/not sure where it will go. I'm sorry, that's me reading far too quickly :/
The only even remotely helpful insight I could offer though would be that you either may have put your email address in in-correctly when registering, something happened on their end that it didn't send or it's lost somewhere in your email (maybe try to search it within your email if you haven't already done that).
Regardless though if you just signed up, I wouldn't worry too much about it right now as it's doubtful you'll get in to the first wave of beta testers, just because by now they should be pretty much done going through them all and sending out emails to the 1st wave of testers.