Mike,
I've been using Mind Manager to manage projects because I can link my
notes, web pages, and external documents and visualize them all in a
very intuitive way. I keep my notes in Mind Manager. So, if 1
particular task in my project needs to link with one particular note
it's very easy and quick. It allows linking in a very granular way.

You can also assign priorities and resources and filter and view them
quickly. The biggest disadvantage is that due dates and durations are
not automatically updated because you cannot make one MM topic
dependent on the other. At least, I haven't figured it out yet.

There is a Gantt chart plug-in for Mindmanager which I've heard is
pretty good, but I haven't tried it:
http://www.illuminesoftware.co.uk/mm/pcproducts/jcvgantt/

Chirag