A really good article for anyone interested in User Interface design on managing complexity. There are some great points raised that it’s not overall complexity that needs to be addressed as such, but rather perceived complexity.
Perceived complexity can be managed by either reducing the actual complexity (removing unnecessary choices etc) or by utilising clean, clear design principles. There is a great example of the UI in Lightroom and Expression Media where they are both quite similar in terms of their overall complexity, yet due to the cleaner and more logical design of the Lightroom UI, it appears to be simpler to manage.