And remember the obvious; practice, practice, practice.

I'm not sure many have chords/progressions as a routine part of their practice sessions but it's helped me a lot. Chord practice [EDIT: always with a metronome] is at the end of my day's practice and follows the stretching drills and scale work. By now that which comes out of the electric guitar sounds really nice, that from the acoustic still needs some work. ;)

The daily chord change practice has made learning songs much quicker.