It will be interesting to see how Google Wave and email will exist next to each other. Even if Google creates gateways the systems are inherently so different that it will be interesting to find out if they can co-exist. Will you get two different kind of groups?. At one hand people who love email for the simpleness. Who love email for all the reasons that Google deems it’s broken. At the other hand the 24/7/365 group. Users who need the adrenaline of being always on, always connected, always part of what’s happening. These are different interaction styles.
Before Google Wave you had email. If you were adventurous you could add IM, FaceBook & Twitter. Each of them adding a bit more adrenaline. But each were different. Google Wave kinda combines everything in one tool which makes it all or nothing. You either Google Wave or you don’t. Doubt you can use Google Wave for just sending emails…
Got inspired for this by Christopher Skillman: