I had a couple of 500 error as well and have to reload.
Another thing I noticed is that, in the registration waiting page, it shows "sign in" on upper right corner, while redirected back to main page after 6 min, I saw that I was logged in Google+ without problem.
And Google Wallet has quite some issue as well.
It may be good marketing campaign for Google, but bad for desperate developers like us. I was even chatting w/ my wife on purchasing air ticket and booking hotel last night.
We want to be there, not for those free stuff.