In a word, ghubalughpalgublbbelplszss.
First, I have to request you get a sound designer or something. Your use of sound effects (or lack thereof -- silence can not be overused) could be much stronger and more dramatic, not to mention your choice of sounds.
The only other major criticism I can offer is that I hope these clips were all created for explicit use in an actual movie. It would be almost criminal if they simply assembled for this trailer and never really put to use.
But that was incredible.
You have an amazing grasp of animation. The jerks and pauses between fluid motion all come together to make solid movement sequences. The tweened stuff, especially in the beginning, isn't nearly as smooth, which is kind of odd considering smoothness is the main thing tweening offers. I'm sure all those seperate body parts are hard to align properly, let alone animate and rotate and keep it still looking human, but in any case they look like the kind of problems that will improve simply with practice.
I appreciate your inclusion of facial features in this animation -- they add great focus to the action scenes right when they're needed most. In sections with less movement they don't add much at all, the emotions seem pretty neutral, which may be intentional for this trailer, but again I think you'll get better at it with time.
Do not stop animating. That is an order.
(Didja ever get in touch with Tom or Wade about whatever happened to the Llama Magic series?)