I just started using GTD using GTDNext and Onenote in order to use the system.
I currently use GTDNext as my task organizer as I find outlook tasks and One Note To Do lists hard to implement the system correctly. However One note is great for organizing thoughts ideas and information.
What would be fantastic is the ability to create a link in the project or task to a Onenote page/section or/also Evernote.
Project: Get a New Camera
Task: Research Cannon (link to Onenote Page that would hold all the Compiled Information)
Task: Research Sony (link to Onenote Page that would hold all the Compiled Information)
Task: Research Nikon (link to Onenote Page that would hold all the Compiled Information)
Being able to link each task to a OneNote Page or section would be really handy as a direct way of clicking and seeing the fruits of your task labor at a click and a glance.
Not sure how or if that would be possible but I for one would find it very powerful and useful. I feel others would as well as from my research into the GTD system a lot of people combine GTDNext and either Evernote and Onenote already. This type of feature would finally create a link between the two.
Hope my idea was clear enough. Keep up the great work. The app is great and looking forward to your Mobile App. please do not leave us Windows Phone Users out in the cold though when you do take your mobile app to market. I see windows Phone Market share will be on the rise especially when windows 10 comes out and sync's all windows devices together I foresee more people starting to make the switch.