I missed it, so some of you may have as well. Over the weekend, NASA's X-43A aircraft reached Mach 7. This represents a major breakthrough in high-speed propulsion, as it's the first time a scramjet has managed to go this fast.
Also interesting, but unremarked, is the fact that NASA's still using their old B-52B for test drops. According to Air & Space Magazine (as I recall), it was beginning to get very expensive to operate this aircraft, as it is the oldest operational B-52 in existence and doesn't share a lot of parts with the models the Air Force has on inventory. The plan was to buy an H model from the Air Force and adapt that, but apparently that hasn't happened yet.