Ok. Here it goes.

All of this stuff seems to be old hat to the embedded guys using other devices besides Nokia tablets. So far, however, nothing much for the Nokia tablets has been posted. I'm mainly posting this stuff here for my own benefit to keep track of what I'm doing, but hopefully others will give it a shot also and post their success (or failure?).

This should be most of the info necessary to cold flash the tablet:

1) First you need a Linux box (or at least a live CD). Then you also need the flasher tool and the pinouts for the tablet, get those at the Maemo Wiki

2) Then you need a 1-Port Serial USB Cable. USB to Serial Adapter with RS-232. You need something with a USB converter chip supported well by Linux. Don't use Silicon Labs CP2102, as they don't support Linux well. You can use either Prolific or FTDI since they are supported well under Linux. Specific devices that work well under Linux are the PL2303 and FT232BM, (that one is noted on the Wiki). There are many cheap cables out there, but since you will need to make certain the RS-232 output is 3.3V, I would suggest using a cable with a chip for which you can find the pinouts and voltage levels. As an example only this one should work. Here is the Prolific PL2303 Product Page. Here are the Prolific PL2303 Datasheets. Using all this you should be able to get a serial connection to the tablet working. USB is needed since a standard serial port is too slow. It would take days to transfer a cold-flash image to the tablet via a standard serial port.

3) Once you have the cable and the datasheet you need to make a connector to mate it to the serial port on the tablet. I haven't got to that point yet since I don't yet have a cable (I'll either buy one locally or mail order for one today), or spring terminals (and a chunk of pcb too) yet and my soldering iron is 3000 miles away

I guess it's time to head out to buy a cheap soldering iron. I'll update the thread as things progress. . .