Finally a competent embedded Linux platform with enough horsepower, memory, and IO flexibility for some heavy lifting. At 2.5 amps, it won't run on batteries (not for long anyway), but it is an ideal small form factor complete Linux system for powered embedded applications.
My primary use is for powered remote (within Wi-Fi range) headless operation so I'm mainly interested in the underlined features for performance, connectivity, and hardware control. The on-board Wi-Fi and Bluetooth are really nice, providing much needed stability to Wi-Fi on the Pi. There's really not much you can't do with the Pi 3. You have full access to the extensive Debian package library. Would be nice if it had a decent built-in A/D converter... maybe next rev. Oh... and a bazillion user community helps.