This isn't a trailer. It's a teaser. And showing .25 seconds of footage at a time is pretty typical for teasers these days.
That said, I will very likely pre-order this one. Metro 2033 was a very memorable experience for me, and probably my favorite game of 2010. Even more amazing was that it was 4A's debut title, their first-ever game; impressive considering the massive technical achievement (it's a beautiful game, and a system-killer for most people.)
The devs say this time around it will be much more polished, and feature more open environments. Sign me up.