ECCP/CCP means Capture/Compare, the pins are triggers off the compares. They are only active if you set them up the right way.
You can use these to create very very accurate frequencies, and can set up to trigger off of a falling edge to create duty cycles. Just read some app notes and the manual, I think you'll understand it. Took me a while, but now that I know, I don't think i'll ever go back to overflow timers again.
With the ECCPs i've made a two axis motion controller based on the 18F8722, while also doing guidance as well as motivation. Once the die issues are fixed this winter, the
8722's HPC Explorer will be my favorite development board to run robots off of.
-Q