A little late for the good deal...I just recieved the 3100cn. Yes it is standard 133mhz sodimm memory. I will probably put a 512chip in my laptop and use the 256 that is in it to up the printer memory.
The printer is good. A little heavy but it isn't too bad once you get it unboxed. I would say the printer itself without the standard paper tray is 50-60 lbs.
At $354 shipped it is definately best in class of all the printers I looked at. Most of the rest had either shady toner use, no ethernet, and not Postscript.
Setup was nothing at all, it even self configured on my network. Installed the drivers, set to Standard TCP/IP printer with Generic Card and it was up and running.
Even at the regular price of $500 or so it would beat the others out there.