Stephen Hawking says philosophy is dead because it is not keeping up with science. The video is here (most of the talk is actually about M theory).
Kaiser says it may be the physicists who dropped philosophy. To a large extent this is all a natural consequence of the academic division of labor.
Many, many philosophers have suggested they are the culmination of philosophy, and therefore that philosophy has in a sense come to an end. All have been disappointed. I think the argument that philosophy has not reached a crescendo, but has simply run its course, has more potential. Of course we'll always have a need for logic and clear thinking. If you want to call that "philosophy", then fine. But as a goal-oriented endeavor (rather than a tool building endeavor) I think Hawking has hit on something. Philosophy ought to be more like mathematics - it ought to produce tools for scientists, and perhaps amuse itself with interesting puzzles every once in a while. Philosophy can also, of course, have a historical dimension too.