I've been struggling with plate spinning for a long time. Part of the problem was having too many plates, the other problem was I never really got to the "trusted system" level. Played around with the GTD Outlook add-in, MLO, Outlook by itself -- nothing was simple/elegant and it always felt like I spent more time dealing with technology than planning my work.
A few months ago, in a moment of complete overwhelm (not kidding), I decided to go back and revisit Franklin Covey's PlanPlus add-in for Outlook -- fully expecting it to fail because it has been very buggy in the past.
To my delight, v6.0 for Outlook works very well and is very well suited to the GTD methodology. It's a little slow but has been wonderfully consistent and sync seamlessly with my Treo. As a result, I not only have a trusted system but I'm following through with my weekly review because I can finally "trust" my trusted system. I can drag and drop emails to the task list to parse into my project lists at a later day, I have project lists for my weekly review. Daily task lists, etc. Also supports categories so if I'm at an @errands or @calls place in time, I'm good to go. I'm about 4 months in and the only glitch I've noticed is that is seems to not like the Netcentric add-in -- but quite frankly I haven't made time to figure out why.
If you havenít checked this out in a while, it might be worth visiting. I just noticed they have a free trial on their site.
p.s. I don't work for FC, I've just spent way too much time trying to figuring out the plate spinning thing and wanted to spare someone else the grief.