Nope, Duck Hunt was never once mentioned in this thread until your post.
I also partially disagree with your assertion that the comparison is completely flawed: while the pointer controls DO add greatly to the game, there's little other reason to buy Reflex, and I would argue that the vast majority of people who cared to do so either purchased or played the game sometime in the past 2+ years, especially since no one really saw Reflex coming until it was announced. Bioshock, which was much less of a sensation than Modern Warfare, was only out for one year, and a PS3 release was heavily rumored (hoped for?) almost from the beginning.
It's not a perfect analogy, but it's far from imperfect.
Too bad I never said the comparison is completely flawed. And why is there little other reason to buy Reflex? If you're a Wii only user, it's your first time having the game on your platform, and it's another Call of Duty game to buy if you enjoyed Call of Duty 3 and/or World at War. And I would agree that most people who wanted to play the game have already played it, otherwise the Wii version would be the best selling by far. But that doesn't change the fact that whether it's a year or two years, Reflex had the advantage of motion controls, online, and one of the most popular brand names in gaming. Bioshock on the PS3 didn't. Most of the hype about Bioshock had died down after the first year, while the Call of Duty hype never stopped for a second (it had actually been kicked into overdrive with the MW2 launch). Also, if your analogy isn't perfect, then it's imperfect.