Jotisz said:The critters were original models scanned with laser and made to 3d. Then ended up animated, textured, rendered and added to the game.
A bit of but check this video it shows the proccess beside a nice interview.
http://www.youtube.com/watch?v=haKOhyUqk4c
Edit a side note
Seems the blue combat armor critter's link is dead
I think they scanned just the faces / heads, and then tweaked them in 3D.
Below is the dude we all love so much, compared to todays standards he is pretty simple model. I can't image they needed to scan this dude. The deathclaws might be another story...