My thought process went something like 'That's cute. Should I bother? Guess not—it's Google, very unlikely to last long.' Seems they may have a reputation problem.

I agree. The fact that I'm signed in with my Google account and it still asks me for my name and e-mail address makes me think this isn't (going to be) a serious part of Google, it seems very much like a 20% project that slipped through.

If you are Google now, you don't get to ask people to show 'interest'. Open it up already and have people try it. Don't monkey around.

Yeah, especially it't not released as some addon to G+, so it might likely to be shutdown in next few months.