The "see you typing" thing disappeared to a large extent from IM clients because it was horrible . Users don't like other people seeing their "thoughts" and it creates a much stronger pressure to formulate/complete an immediate answer. And the "robot" thing is just inane - it's not like bots are hard to interface with e-mail or with the web; it's just that at the current level few bots are very interesting beyond the…
The robot thing is not inane because it is part of the distributed/federated document editing, and it has media elements attached to it rather than just text. In IRC, you only talk to people for the most part, so bots in IRC are centered around facilitating that purpose. With Wave, you talk, work, and plan with data that can take any form - a much broader scope that allows robots to do much more than just 'user logged in, user logged out'.
The reason why I think it is a strong alternative to project collaboration tools is because of 'see as you type' and its robot capabilities. Yes, it has a nice document model, but that isn't the key feature for me.