My friend Gernot Starke is delivering a presentation on communicating a system's architecture to the team and stakeholders. Good talk, as usual, very much focusing on "soft" issues. One question from the audience from the audience was interesting and went unanswered because it was out of scope, but it grabbed my attention: What's the right tooling to document an architecture? MS Office, i.e. Word? Docbook?
Considering all the different tools that I have used in the past, my vote would be to use a Wiki, without a moment of hesitation. Seriously, why would anyone willingly choose something else without being forced to do so?