In the modern world, and especially online, privacy is quickly becoming a thing of the past. Almost every click or site you visit is recorded somewhere in some way, and I do not think that the state of things will change anytime soon. I do think that there are some privacy considerations when using Google Wave.
Google Wave is both a step forward and a step back with regards to privacy. The fact that Wave uses a secure channel for all transmissions means that your aves are safe from prying eyes. Of course, the actual information is still stored on the Wave server (at this stage i do not know if it is stored encrypted or unencrypted), which of course raises the issue of how secure the server is, and how much you trust the company controlling the server (currently, most likely Google, but I think that will change as more companies start using their own Wave servers once the technology is fully ready for that).
The nice thing about waves is that it is possible to limit who you invite to a wave, and that way ensure that a discussion stays private (so long as you trust the other participants). Be careful when inviting bots, thought, since they are also able to see the discussion in a wave (although not in private blips, unless explicitly invited to them), and often log stuff from the wave for troubleshooting purposes. The couple of bots that I have seen that do this are very open about it, but it is something to keep in mind when using them. Of course, bots are unable to see private blips that they are not invited to. Extensions do not have this issue, since they cannot see anything of the wave they are in that is outside them.



