Elrond Hubbard Kinetic Typography Tutorial from Crooked Gremlins
There is a second video and this is also in text version at this link:
http://cvhsdesign.edublogs.org/assignments-2/advanced-graphic-design/kinetic-typography/
Kinetic Typography Tutorial from Elrond Hubbard on Vimeo.
Staring with laying out text in Adobe Illustrator
How to animate starts about at 9 minutes in.
Keep each composition length the same.