I've done the switch - rmmod the g_file and insmod g_ether. It sometimes works once, but not long enough for the PC to recognize it (The Nokia update wizard has the RNDIS drivers for the n810). Sometimes it reverts to the filesystem, too helpfully reloading the file module.

I'm not doing this early in boot.

Has anyone else gotten USB as network to work on the n810 with the latest OS2008?