Today, NCsoft has lifted the veil on their Mission Architect system coming in the free Issue 14 update for City of Heroes -- which is currently looking at a March 2009 release.
Massively.com has both a shiny collection of screens and a nice juicy hour-long audio file of Joe Morrissey discussing the various (and numerous) ins and outs of this hugely anticipated feature. Massively.com has also distilled the most pertinent information into an easily skimmed list.