I remember the new Basecamp having the same problem just after they launched (it's gone/fixed now), maybe someone from their team could chime in on how they solved it?

Hmmm. Not sure what you're referring to. We've made some improvements (http://37signals.com/svn/posts/3137-using-event-capturing-to...), but nothing specifically related to the editor/Chrome.

Hmm ok, well the first two days after you launched the editor had some lag for me on Chrome on my MBA, especially the time from clicking the editor until it expanded and let me type would last 1 to 3 seconds and typing itself had some lag too. Anyone else had this problem?