Hi, I'm also having this problem (Chrome 12.0.742.122). The funny thing is, it was working fine until yesterday. I even removed all my modules and the problem was still there. Here's the JS error log, seems like the same problem someone above was having.

Uncaught TypeError: Cannot read property 'height' of undefined (LeftAndMain.js:186)
Uncaught TypeError: Cannot call method 'match' of undefined (prototype.js:1100)
Uncaught TypeError: Cannot set property 'display' of undefined (LeftAndMain.js:769)
Uncaught TypeError: Cannot call method 'match' of undefined (prototype.js:1100)
Refused to set unsafe header "Connection"

did you try the layout_helpers.js-modification?

for me it seems like a bug in chrome...

It started working again without even having to change anything. Maybe there was a bug and the Chrome devs fixed it.

I have been able to use chrome to edit the CMS, but the only issue I have is that the Image pane and link pane opens behind the Page Tree pane. Every other browser I try it works fine. Its annoying because chrome is my preferred browser, but I have to use FF if I want to place any images or links into the editor.

Mostly annoying, but would be really sweet if I could find an fix for it.

hmm,
have the same problems with Chrome, but the errors differ a little bit.
Started to use it in IE8 - everything is fine...