Not to make a "late hit," but I should have pointed out something earlier. Colbert's 1953 lament about the lack of any sign of fossil history for whales stems from the necessary prediction of evolutionary theory that intermediate forms must once have lived. They may not have been preserved in the fossil record, but they must have once lived. The lack of any such finding to Colbert's day and into the late 1970s thus amounted to an unfulfilled prediction. (There were fossil whales, some of which had features such as vestigial hind legs marking them as more primitive than modern whales. All were clearly completely aquatic, however.)
The finding of Pakicetus (terrestrial) and Ambulocetus (about as aquatic as a crocodile) in the Tethys Sea fossil beds of Pakistan and India fulfilled the prediction for such forms. Just another case of a pattern of events often observed by now.
For more fulfilled predictions, check Is Evolution Science?
The biggest -- and to me the best -- example is the hoary old claim of the creationists: "You haven't found the missing link!" This is important for two reasons: (a) creationists made their one big prediction that no intermediate (sub-human) species existed; and (b) evolution predicted that such must have existed, and that perhaps one day their fossils would be found. A perfect setup for the creationists to test their "scientific" theory.
But now that this one crucial cornerstone of creationism has been shattered (i.e. special creation of man with no intermediate species), they still won't give up. They never do; they never will. And they never make predictions any more -- except for one, which is technically outside of evolution theory, but not "creation science." They all predict that life can never be generated from non-living material. If that little trick ever gets accomplished, and the creationists are then batting 0 for 2, they still won't give up (that's my prediction).
Yes, and I'll bet these finds are absolutely conclusive, no possiblity of misinterpreting or reading into the find!