Hi zethrix,
well that s a few question here 
Avatar was a great experience, I really like James Cameron’s movie, especially Aliens, so when I heard about a new Scifi movie from Cameron coming our way, I started asking everyday my Head of Department to be part of the team. Eventually I got assigned on the show, and I got to look at the material. It was outstanding. We also got invited by the studio to watch their WIP in a private cinema. I was shocked how beautiful the environments were. It was my first stereo project back then.
As far as work goes I mainly worked on very distant background around the human base. toward the end we used dmp projection to add the last minutes extra details on building/ground.
Dylan Cole. I never met him, but I dont know of him
we never worked directly together.
I bought his children s book for my kids. I think he is a very talented artist and I hope we ll get to work together at some point in the future.
TV vs Film. For me, Film is why I joined the vfx industry. How cool can it be to have worked on Lord of the Rings, or Harry Potter, Star Wars, etc… The reality is that you dont get to work on that many cool film.
I used to prefer working on film, but since I got the opportunity to work on Game of Thrones, I am more open. GoT is such an amazing story, it is a dream project for any matte painter, you get to do all those really amazing wide scenery. If you haven t read the book, I highly recommend you do, it is even more outstanding than the TV serie.
Pipeline. As I said in the previous email, it depend of the facility or the project. I use a mixe of Photoshop, Maya and Nuke to get the work done. But you need to keep in mind that it is a team work. You might not be doing everything, sometimes it is an other department that provide the assets, sometimes you even got a textured render to work on top of it. In Matte Painting 3, David and Milan are covering various situations we can meet.