One of the biggest gripes I get about implementing Web 2.0 in an organisation (not just museums) is the time it takes to do Web 2.0. I have already answered that question on the Project AMEP blog post
(i.e. 12 minutes and week + 2 large glasses of red wine!), but another idea I'm toying with is the notion of write once, publish many times.
I have attached a model that Bliss and I developed after working on our Project Evil
audience research and be interested in feedback and comments. We're writing this up further for the next edition of the Exhibitionist