A new user's experience
I got to you through James Fallows, who's singing your praises on his Atlantic blog. In any event, in IE7, my wiki looks nothing whatsoever like your demo. In particular there is no config button visible, which makes the whole thing useless, as I can't define contexts, tags, etc. Not quite ready for prime time, at least for me as I'm unwilling to download a new browser just for this. Nice idea; I like wikis generally and having my GTD system online rather than in a standalone program would be a huge plus for me.
Well the demo has some example projects and actions. When you download an empty MonkeyGTD it starts out with nothing in it. You create your projects and actions using the [+] buttons or the +project and +action buttons at the top. To create new contexts click on the "Process Inbox" tab on the right sidebar and click 'new context'. If you ever want to give it another try then please send me an email. I'd like to help you get started and perhaps learn which parts of the interface are the least intuitive from your perspective as a new user. I agree that MonkeyGTD is a lot more usable in Firefox that in IE. This is something I'm hoping to rectify in the future. Thanks very much for posting your feedback.