Recently our efforts was split into developing and extending Emaily as a robot and working with the Wave team on some other cool thing which I cannot tell right now. But yes, it is related to emails. ;)
On the Robot side, we managed to finally stabilize it, so that we feel it is now reliable and usable with basic functionality. We think that we fixed all the errors we saw recently in our console and for now, you have a reliable email to Wave and Wave to email gateway. We do expect standard emails to arrive properly (normal means not too big, not specially crafted, etc.) and that wave updates are sent out reliably.
Email recipient handling vs. Wave participants
Email is different than Wave on how it deals with recipients/participants. Thus, any integration effort between these systems has to have tradeoffs. We figured out our way of handling email recipients, and we think that this approach handles some very common cases, though definitely not all.
One of the goals of the robot is to be as transparent as possible without being confusing. Starting from this release, when someone answers to an email which was sent out from Emaily and adds more email recipients to the reply email, then the robot will add these people to the conversation. Starting from that point, these people will get all updates on that wave and they can even reply. There is no current way of unsubscribing from a wave from email, but wave participants can remove any email participant, so you just need to ask someone.
The same works if this is a new email which arrives to your Wave. If there were more recipients, you will see them as wave participants, so when you answer, everyone will get the answer.
There has been a lot of work done recently on the most requested features also: rich text emails and attachments. Actually they are almost ready.
Two weeks ago, we had a 4-day hackaton, where a team of 6 people worked on Emaily, and the biggest achievement was the development of these features. They require some polishing before release, but they are definitely around the corner!