Edit This Page was the central feature in Manila, the blogging tool we shipped at UserLand in 1999. For me, a blogging tool without it isn't much of a blogging tool. But it's not easy to implement. C'est la vie. Neither was Undo, but the Mac required it, and it's one of the reasons people like the Mac.
The premise was that every story in the system would have an ETP button that, when clicked, would open the story in an editor, so you can make the change, hit Save, and get on with it. Content management systems of the day didn't have that feature.
Programmers may not have a problem with this duality, but writers, non-technical people, had a lot of trouble with it. ETP removed the duality. When you see something that needs fixing you just click a button to make the change.
Anyway -- Scripting2 will have that feature as well. I'm getting started implementing it, so if you look at the HTML source for this page, you'll see a <script> element that links back to the local server, 127.0.0.1. If you don't have a server running there, hopefully your browser just ignores it. That's one of the reasons I'm writing this post, to see if that assumption is true.