Today, it requires 2000 reputation to edit questions/answers; most users don't have that much reputation.
Quora allows anyone to click on a "Suggest Edits" button; it launches the editor and privately emails the author with the suggested changes. With one click, the author can accept the edit right from the email. It's quite nice.
For example: http://www.quora.com/How-does-Twitter-make-money
SE should have a "Suggest Edits" button, too.
[status-about-to-be-completed]
as per minor bugs like Pending edit does not reveal any changes, maybe due to edits in grace period? (and its comments).