Though it uses some open-source parts, Safari itself isn't an open-source browser. Although KHTML is a decent, fast engine, it tends to lag quite far behind IE and Gecko (Mozilla's engine) in terms of support for javascript, and contenteditable, which are a huge part of what make up the editor.
Jason Rhinelander
Gossamer Threads
jason@gossamer-threads.com
Jason Rhinelander
Gossamer Threads
jason@gossamer-threads.com