Josiah Carlson wrote:
...in the cases I have seen ... you _always_ get them in RGBA order.
Except when you don't. I've had cases where I've had to convert between RGBA and BGRA (for stuffing directly into a frame buffer on Linux, as far as I remember).
So it may be worth including some features in the standard for describing pixel formats.
Pygame seems to have a very detailed and flexible system for doing this, so it might be a good idea to have a look at that.