Just posted the below on the official forums. I know a lot of people feel strongly about this, so if you do, head over there and bump the thread.
(TL;DR at bottom)
As someone who plays a male Night Elf I was discouraged when I heard rumblings from beta players about them having a lackluster model--especially combined with the fact they weren't given an artcraft. Even more concerning, however, were the videos pointing out their new run animation. I logged in on patch night and was pleasantly surprised with the new model. Keeping the art team's main goal in mind--to "update" models without sacrificing their identity--I believed people had overreacted, and that the transition was pretty faithful, overall. What I hadn't expected, however, was for this goal to be compromised to the extent it has been by such a major revision to the run animation.
First, let me say, I applaud the team for taking on new character models. It's an incredibly challenging task from the outset knowing there will be inevitable backlash based on people's strong feelings of attachment to their avatars. Also, the team did a great job. The models look excellent, overall, and succeed when it comes to their primary goal, mentioned above. This is why it is somewhat baffling to me that the team spent so much time adhering to this philosophy only to revise some race animations to the extent that the characters no longer feel like the ones we've grown accustomed to playing.
At the end of the day, new models are very important. We all love to pan around in our favorite transmog and check out the new faces and detail, but in reality, it is the movements of our (almost always armored) characters that we've been experiencing throughout the years. In the case of the male Night Elf--and there seems to be a consensus that it is the most egregious, though I've seen other players voice concern over other races, male Trolls for instance--the animation feels more akin to a Pandaren, and in my opinion, not only feels rushed, but completely illogical for the demeanor of the race.
TL;DR: Some of the new run animations are such a departure from what we've grown accustomed to that they compromise our ability to enjoy the new models.