Got my E5345's and installed them today. Pretty hassle free following the Anandtech guide. Had to figure out the long 3mm hex. I found a 3mm hex bit, cut a slot in the base with my dremel and then inserted a long slot head screwdriver and duct taped them tgether. Worked ike a charm. Duct tape... not just for ducts anymore
Handbrake is much faster now. With the quad core I would take about 35 minutes for an average movie with 70% quality. I just encoded "Oceans" in a little over 15 minutes. Definitely going to be saving me a lot of time.
Can't really notice if there is a difference in menial tasks in the OS so far by dropping from 2.66GHz to 2.33GHz. That is going to depend on how well Snow Leopard and my Parallels/Windows7 applications make use of the cores.