But I'm also glad that I didn't have a stake in it - It had to be an unsettling investment for those who did. It's got to feel good to have participated, but it was obviously a gamble from the beginning. Watchmen is definitely aimed at a niche market.
On the contrary, it was probably a pretty predictable quantity compared to other movies. Not that any new release is predictable, but this one wasn't anything like 300 or Sin City where they were hoping to pull in people who knew nothing about the source material, or like Persepolis where it was unknown whether the enthusiasm for the books would last through the release of the movie (and where there was probably a lot of doubt that fans of the books would even bother to see the movie.) It was a so-so movie based on a popular and prestigious graphic novel. They knew the size of the niche. They knew that the readership of the graphic novel would contain more movie fans than the general population, and, having test-screened the movie, they knew it wouldn't break out to a broader audience or inspire massive rewatching.
Assuming that the broadcast and rental rights were sold before the film screened, the DVD sales are probably the riskiest part -- how many people want to see it again? Will fans of the graphic novel want to buy a movie that failed to do the source material justice (inevitably and maybe blamelessly, but still)?