I was lucky enough to receive an invitation to Google Wave recently, and logged in for the first time today. I actually quite like it, but there is a lot to learn. It has a lot of potential; apparently, you can embed a whole wave into your blog so your blog readers can participate in the wave. It also interfaces with Twitter (actually, it can interface with anything with an API) and one video I saw demonstrated a language translation feature, allowing people to communicate who don’t speak the same language.
I’m going to have a lot of fun learning how to use this!