I'm like you in that I've been playing with some PIM or another since 1999 (yes, it was a Palm) and now I find myself using a host of products that...again like you...includes Toodledo, Gmail, Gdocs, Evernote, among others. Instapaper.
Collectively, I've accepted these various tools along with my UCD, paper files, bulletin boards, white boards, etc. as my "extended mind" (which we all know is a better place to keep things than "psychic ram") with Toodledo being the root directory that keeps them synchronized via periodic "crawl" reviews and "scan" reviews (these are of course repeating taskers in different contexts).
You've gotten a lot farther than I have, though, where the rubber meets the road - action. Well done. Will be rereading your article again more slowly here soon (web clipped via Evernote, forcing me to evaluate again during weekly review when I process untagged, unfiled notes).