OK, actually I could not resist and gave it a try
First of all: updater will work as well on Windows 7, you just have to make sure it is running from elevated command prompt (run as Administrator) with -t COMX option (X is modem port number, for me it had to be actual modem port, not management one).
It is also important that "WWAN AutoConfig" and "Mobile Broadband" services cannot be running - otherwise they will hog access to modem port and updater will not recognize device.
I started update process, it uploaded firmware just fine, but after *device reboot* it just got stuck at "awaiting for device to perform firmware update" - eventually it went to 100% and I got an error that device didn't came back after update.
At this point, I was pretty sure everything is over
However, suprisingly device is still alive!
AT*EVERS shows now new R1D06 firmware revision and 3g connection still works - I will test stability and report back