The true colours of dinosaur feather have in fact already been revealed a few times - the first time ever in Sinosauropteryx in 2009. See a.o. this National Geographic story.
Feathers is one thing, but could it fly? A research team from the University of Manchester has carried out calculations which showed that the feathers would have been too weak for flapping wings. They were only barely strong enough to support gliding from tree-to-tree.
Their new study published in Science on 14 may 2010 suggest that the fossil birds Archaeopteryx (Late Jurassic - about 145 million years ago) and Confuciusornis (Early Cretaceous - about 120 million years ago) although they had feathered wings resembling those of living birds, only had poor flight capabilities.