Just noticed on the Sony US site a bit about a kit for the EX3 to improve tripod mount stability called the HPMWEX3/1.

Sony | Micro Site - XDCAM EX (http://pro.sony.com/bbsc/ssr/micro-xdcamexsite/)

Yep, this got discussed at great length a while ago. I'll add the link in if I can quickly find it.

http://www.dvinfo.net/conf/sony-xdcam-ex-cinealta/234679-ex3s-shipping-tripod-mounting-fitting.html

Seems two of the 4 items in the kit are back ordered.

413723601 QT:BRACKET(S) , TRIPOD 1 $11.53 $11.53

413723501 QT:BOTTOM PLATE PROF HD CAMCOR