The time scales are interesting from a user point of view. On the one hand, DSLR's with much better image quality have gotten so large that a Leica S2 "MF" camera is now smaller than some of them.
Looking at best choices from the lower end, in April 2005 I could buy a Casio pocket camera with 35-105 equiv. zoom and 10 mp on a 1/1.8 sensor, then 4 years later buy a Panasonic with 25-300 equiv. zoom and 10 mp on a 1/2.33 sensor.
So what did 4 years of tech improvements bring?
Zoom, fantastic. Opens up whole new worlds of opportunity. For DSLR's, the smaller size and improved stability of the zoom lenses is good news.
Zoom motor, still poor. Thankfully my zoom on the G1 is manual. The GH1 is another matter.
Image stabilization, all good news.
Size of camera, slightly thicker, still pocket size. DSLR's are now available in ever-smaller sizes.
Quality of image, same or slightly better, and no worse noise. DSLR's with smaller sensors are improving a lot.
HD video, stereo wideband sound, all good. HD video is moving into most DSLR's now.
Battery, about the same. The bad news is, most of the smaller "DSLR" cameras like Pana G1 and Oly Pen have a short battery life.
Memory, all good news.
Transfer speed, much better.
Screens are much better now.
Flash, little or no better. Not very practical to use external flash on a pocket camera.
DSLR's will continue to do some things that all-in-one cameras won't do anytime soon, like use special tilt lenses etc. But most other features will float up or down more or less equally. And even if sensor and per-pixel image quality don't improve a lot, the smaller and better-stabilized zoom lenses are bringing new worlds of opportunity to walkaround shooting.
Maybe it's time to say that DSLR's have become the medium format of the present, and the official MF designation has moved into some other territory.