Ive got to agree with Alan's first post, I feel theres lots of modeling tutorials already on the site, theres lots of hard surface, organic, low poly etc etc.

I would personally like to see more advanced rigging, dyanmics, possible hard surface animation mixed with dynamics, say a car crash, explosion etc as these are a big part in TV, film and game work.

Or even a tutorial on photorealistic texturing and rendering using mental ray with the textures being generated from photos and the environment from a HDR/LDR image made from scratch and the object being compositied into a photograph, as ive not really seen many other sites offering a tutorial like that??