I come from a programming background. Initially had planned to use a PIC chip but it had a modest learning curve.
Having used Linux for over a decade this just seems perfect. It can control the camera over USB via gphoto2, GPS, and there are a myriad of sensors also accessible via USB.
After reading info in other threads it seems it may also offer SPI/GPIO so if I wanted to go a little lower level that's still a possibility.
R-Pi is truly a beautiful piece of engineering.