OP, sorry to hear what happend to your carry-on. United lost my bag once as well, and I know the feeling of waking up in the middle of the night, checking the status of my lost bag. However, mine was just on plain, boring O'Hare, while yours got to travel to Whitehorse, and even came back with tags, proving that it was there once.
Anyway, great rant and hopefully we'll read a lot success stories after this