You said: we’ve moved from e-mail, to instant messaging, to texting, to Twittering.
The difference with Wave is that it is not just a new tool to communicate, but a way to solve some of the problems with our existing communication tools and methods. That’s why I think it stands a chance of success.
In the social arena, it’s interesting to speculate on the future of SMS texts – will they stay outside the Wave? As 3G becomes more widespread will Twitter (or similar) replace SMS?