Google Calendar is out and it's good. Compared to 30 Boxes, the only thing it seems to be missing is tags. The behavior of the interface isn't as fun either. It's still got single box entry (which even seems smarter than 30B's), and the sharing is way more powerful (except for the lack of tags - that's one of the best things about 30B, you can share events with certain tags with certain people).
After more playing, I've found I am unable to add my Upcoming events to the Google Calendar, even though I should be able to...