Actually Canon did that going in with it's eyes wide open, they knew that in lens focusing was the better method, so they choose to move their entire line to it. It was a business decision, do you piss everyone off at once and be done with it, or piss a smaller section of people off over time as Nikon has chosen to do. So far neither method has cause much problems with eithers bottom lines.
I think that's apples and oranges. Canon changed its mount entirely. Nikon is just removing the ability autofocus from some lenses, not changing their mount.
Not to say that Nikon isn't pissing anyone off, but DizzyV6P seemed to be putting forth the idea than Canon had never done anything to piss off their customers. Nikon has actually never changed their mount, and are the only ones who haven't.
FWIW, I did a little research recently and basically all of the "big five" have changed their lens mounts at least once.
Canon: 1959-?, R mount; 1964-1971, FL mount; 1971-1987, FD mount; 1987-current, EF mount
Minolta/Sony: 1958-1985, MC/MD mount; 1985-current, A mount
Nikon: 1959-current, F mount
Olympus: 1972-2002, OM mount; 2003-current, 4/3rds mount
Pentax: 1957-1975, M42 screw-mount; 1975-current, K mount
So, only Nikon didn't change, Canon changed more than anyone else. I believe that Pentax is the only that to this day, still sell an adapter to use their original mount lenses on their current mount (and references screw-mount lenses in the custom menu on all their DSLRs.) Olympus' 4/3rds system is the most adaptable, with third-party adapters available for most other mounts complete with infinity focus, but they're pretty expensive. Adapting other lens mounts on Canon and Nikon usually loses infinity focus without an extra optical element (reducing quality). I'm not sure about Minolta/Sony adapters.
I do think that it's pretty shameful that Nikon decided to pull the focus motor from their entry-level cameras, and I won't believe that it's an attempt to force people to upgrade, but rather a simple cost-cutting measure. If they start to remove the focus motor from any models
other than their cheapest ones, then maybe I'll believe it. Note than the newest non-entry cameras, the ~$2k D300 and ~$5k D3, still have a focus motor in the body. It's too bad as it's always a "gotcha" when discussing the D40/D40x/D60.