Ah, I don’t use any of those so I guess I’m just out of the loop. I got a Gmail beta invite back in 2004 and used it for a couple days. Didn’t like its threaded system and lack of compatibility with my browser. I was an early adopter to Google and it’s still the only search I use so I’m not hating.
Thanks for sharing this demonstration clip! It seems like an awesome consolidation and unification of existing systems into one concept, which seems to handle all the specific use cases with grace. As a long time internaut and programmer I can really see the usefulness of this instead of having separate systems for each of the tasks Google Wave can handle, as well as the power of its extensibility.
After watching the video there were just a couple of issues that I noticed, which I am sure the developers have considered (maybe I just misunderstood).
First of all, the collaborative editing seemed to be on by default and as far as I saw they didn’t show any extensive system for handling editing permissions. Maybe somebody can explain. Is the original Wave creator the only person able to modify a wave until he/she adds other participants? For example, there needs to be a way to give some people read-only access to a wave. I am sure the google fellows have thought of this and that there will be good solutions as soon as it is released.
Secondly, both a strength of Google Wave and a weakness is the central storage of all the content. The problem I see is that I might want to share photos with a friend, without having them stored at Google’s (or another Wave provider’s) servers, the same actually goes for all content. I assume the only solution for this is to run my own Wave server for my own and friends’ content. I suppose different collaborative online projects will have their own servers to keep content private. That might help some storage privacy issues, but it still feels incomplete for me, and I don’t think it’s addresssed in Wave.
I watched the keynote speech on youtube today, and applied to be a tester. I wrote a limerick 
Anyways, to answer some of your queries with what (I hope is correct) information:
Not all of the information would be stores on Google’s server farms. This point actually surprised me a little bit.
There’s a small demonstration in the keynote where they introduce “ACME”, who is using a clone of the Google Wave system, since it’s open-sourced and easy to manipulate. They can communicate with each other and interact as though they were all on one “wave”, so to speak. They also introduced “initech”, who coded their own interface using the command line. Lars then proceeded to explain that even if the inital “wave” started on the Google Wave server, and participants were added from other servers (hosted elsewhere), if there was a personal discussion between two people in another server within that wave, it would stay in that server, and would not propogate to the other waves.
That is:
Lars starts a wave on Google and adds Sarah (from ACME), John (from Initech), and Bill (also from Initech).
If John and Bill split off and have their own wave WITHIN the initial wave, that information stays on the Initech servers, and there is no way Lars and Sarah can see what John and Bill are talking about.
I watched the video. That’s what I meant by running my own server, instead of using google or initech, or whatever.
I just realized something. What if this could replace that abomination known as the Conference Call? Think of it! No more listening to people snuffle and tap their pens on the table. No more wondering who said what. And having a record of what was said, and who said it.
I can get on board with that.
Maybe… but Wave doesn’t seem to have any support for audio. The best you could expect would be the same meeting/conference call, except everybody has a laptop, and is editing the document together, while discussing it in real time over the table/phone.
Wave might make things faster though… so you may be in the room less often?
Worse yet, virus and trojan writers.
When was beta testing going to start?
All this caffeine in my veins is making me anxious!
I was thinking about the discussion being in the wave … not necessarily documents. I suppose if you were working on a document, you could have the document in one, and open another session with the discussion only. I don’t think the audio part of a conference call is any advantage.
Looks awesome.
Taking a bunch of stuff people already do, making it all more user friendly, and making it work together better is a big deal. That’s essentially what Microsoft did with Windows.
This looks very cool, and it could easily become the new standard interface for web-based communication.
Meanwhile, the latest innovation from M$? A search engine and a nine-figure advertising campaign behind it.
I guess I’m just not seeing the big deal with this. Then again, I rarely use e-mail or instant messaging, and I never use facebook/myspace/etc. The ‘threading’ in my gmail account also drives me nuts. I’d still use my basic 1998 hotmail account if it weren’t so flooded with spam. Just isn’t a product for me.
What was your haiku?
A replacement for email will likely be more proof of spam, presuming that Google designed it correctly.
Even though it’s been a few days, I’m still anxious for this info. 
Mine was:
A pebble drops in the sea
The wave ripples out
What far shore does it break on?