Just browsed a bit in the thread, and felt I ought to add a few points. I've been sculpting dino's professionally for over 20 years, and have quite a few friends in the field, so I get the good stuff...
Feathers on T.Rex...Nope.We have samples of tyrannosaurid skin. Said samples show fine scaling, roughly like a basketball, though more tightly packed and less uniform.As a side note, scales and feathers are mutually exclusive;that is, one cannot supplant the other on the same patch of skin. This has been proven as fact, much to the chagrin of the bird-boys at AMNH...
Scar has it right as to running speed for large predators.While Rex would have been the fastest of the large carnivores, that ain't saying much. Interestingly, Greg Paul(who's one of the cheer leaders for speedy dino's) had the jeep chase from JP analyzed to determine just how fast the Rex was moving. He was rather annoyed to learn that it works out to a blistering 12 mph(still faster than your average human, though with THAT behind me I'll bet I could do it!). He was even more annoyed that the guy that did the actual work released the results.
I recently finished up a project for the Museum of Science and Nature in Raliegh-Durham. I produced a series of macquettes for their dinosaur trail. These sculptures were enlarged to full scale by a sculpture house in Canada.The trail opened this past summer. Anyone interested in pix?...PS