All credit goes to Wysie for this. Myself and Cennis91 were just the people who poked him to do it. This has only been tested on CM 5.0.7 so no claims for it working on any others. It was built with CM code.
So here it is, a camera.apk with a setting to toggle the ultra-annoying BOOP BOOP focus sound. Again, all credit to Wysie! his contact info is:
Twitter: Soh Yuan Chin (Wysie_Soh) on Twitter
GIThub: Wysie's Profile - GitHub
So without further ado, the camera.apk: http://www.mediafire.com/?zzd04mmamg1
And again, please remember Wysie was the one to pull this off.