When attempting to copy text with Apple-C, WebKit crashes. Doing so via the Edit menu does not cause this behavior. This happens every time without exception, so is very reproducible. I've seen it in the last few nightly builds.
Can you please provide explicit instructions on how to reproduce this crash? I was able to visit this bug report web page in the latest nightly build (r40534), select the entire page, and copy the contents to the pasteboard via Cmd-C without a crash.
You can probably close this bug, actually. It appears this is caused in WebKit by having Google Gears installed. I just removed Google Gears and this bug appears to have disappeared. I will reopen if it shows up again.