This is my issue, though. I don't really think people did. They'll buy the new hot thing; I find 'loyalty' laughable.
I think the Playstation brand was much stronger back then, right before the PS3 shipped, so I find it believable. I think many expected what happened between the DC and PS2 to repeat between the 360 and PS3. I don't think it's any coincidence that much of the PS3's announced specs were roughly twice as much as the 360's specs back at E3 2005. Between all the talk of super computers, how the 360 and Wii were toys, xbox 1.5, etc. Sony was trying to recreate what happened with the PS2 launch.
I agree with you on the whole loyalty thing, but look at these threads and you can see it everywhere.