BT, beat me to it :-)
Finally, something new. Although this is Marvell's driver, still it shows that Intel isn't (completelly) sleeping!!

Paul
ESs used to be higher binned chips in the past, now like you say they're test samples I believe. They give them out for reviews and internal personnel I guess.
That must one hell of a crunching monster still. Don't know about TDP though, maybe it still fits the normal envelop.
By now, with the latest BIOS, you should hardly go wrong with any mem brand and model. I had problems with my OCZ kit at first but not anymore. Corsair should be fine as well. I guess anything with Micron or Elpida chips will do just fine.
Maybe you can test the mem before you buy. Not very usual here though.