about.com is a dead-end site that has been eclipsed by Wikipedia for two reasons.
First, about.com is littered with far too many ads which makes it an unpleasant experience to use it.
Second, Wikipedia has a much larger number of editors resulting in more complete, and most importantly, more current information. about.com tends to be stale and out of date.
I don't see that about.com has anything of use to contribute.