Some thoughts on WCG benching - HTH.

Fallwind's "BOINC data snapshot" method is definitely the most accurate way of comparing crunching speeds. I did this a while back to compare speeds under XP-32 vs under XP-64 + 64-bit client, on the one QX9650 machine. (64-bit was about 0.5% faster, for HCC).
So you definitely can run the same set of data on 2 versions of Windoze on the same machine.
However, Linux BOINC data files are not compatible with Windoze ones, so you can't compare across these OSes. I don't know about Linux vs Mac OSX (both *nix).
I don't know whether you can run the same data on different machines with same OS. I know the BOINC system is fussy about device IDs, and won't let you crunch, upload and claim WUs from the wrong device, so you can't do "sneakernet", but it may let you just run foreign WUs. (I forget whether, in my win-32/Win-64 comparo, I had to give the machine the same LAN device ID)
Remember NOT to let BOINC try to upload the same set of results more than once. Run tests with network activity disabled.

To make results comparable, whether using the data snapshot method or credits awarded/hr, you need to be running the same mix of WCG projects, especially with HT (critical). Even without HT, different projects need different amounts of main memory access, and hence get different amounts of memory bus contention. Example: On my A64X2 (512kb cache/core), PerfMonitor 1.0.0.8 shows that HCMD2 gets 99.6% L2 cache success rate, while faah gets around 87%.
Easiest is to run just 1 project.

If wou want the most accurate comparisons without using the data snapshot method, and a minimum number of WUs crunched, I suggest:
* Pick a project with a quorum of 1. If HFCC has moved to Q2, I guess that leaves faah.
If that's unsuitable, pick a project with minimum variation in run-times. HCC scores here, but you'll need a larger sample size to average out the wingmen.
* If using a quorum of 1, look in your Results Status pages (not Device Stats), and pick out only those valid results that had a quorum of 1, ie don't count check-WUs or repair-WUs where a wingman got Invalid. That eliminates the wingmen.
Then calculate average Credits Awarded/hr.
There is some variation in CA for faah WUs of the same length, and I suspect that longer faah WUs get higher CA/hr.
There is probably variation in CA/hr between WU batches, too. See Sekerob's Charts.

PS 1: To avoid confusion when talking about BOINC or WCG "points", note that BOINC calls them "credits", so I suggest you use these names too, ie 1 BOINC "credit" = 7 WCG "points".
PS 2: I was hoping that i7-860 would be a clear leader in energy/credit, but it seems to need more volts than 920 @ same clock, and crunches more slowly. I'll stay with LGA775 until 32nm.
PS 3: Thanks for all of your work, as well as being first kids on the block to risk forking out $$ for Lynnfields.