So the blackberry is going very well.
The keyboard/suretype works great, I've written a speach on it, and use it for task tracking regularly.
I'm using the google calendar / outlook synchronizer and that works well, except for being dead slow.
I'm trying to implement the context lists, as recomended by GTD, and here's a shot of my task categories as it stands.
You can 'filter' your tasks by a single category, which is a limitation, being able to filter by 'next actions' and 'waiting on' and 'office' would be good... the gmail plugin does that better. I'm considering getting a gmail account JUST for GTD tracking.