When Wave was announced I passed on wave invites to android developers. Thus, lets give out some Google+ invites although the invite service will not be back up for several days I can collect email addresses now and have Google send out the invites. I have left about 200 invites, so the first 200 android developers who in this post add a comment with their emaill address and the name of the android application they are working on will get an invite to Google+.
Once you receive your email invite from Google, star that or mark that email and just keep trying each night the link in it until you get in. It might be even less than 3 days.