Right after wave is announced, I remember google-wave-api having more than 100 emails a day. After a while, the email volumn went way down, presumably because people who receive wave sandbox account have moved the discussion to firstname.lastname@example.org. Since last week, I have noticed that the volumn is up again. This is a good sign. This may be due to arrival of new sandbox accounts. Or it may be the due to shutdown of email@example.com.