The minimig is not perfect in many ways, but it's a damn good piece of kit and I would not hesitate to recommend anyone to buy it.
The compatibility problems will eventually be sorted out, and you'll all be able to upgrade by just replacing a file on the SD card and rebooting the MiniMig.
The menu structure is a software matter and, PIC memory permitting, could also be sorted out given time and volunteers. Likewise for implementing a hardfile on the SD card or using 2GB+ SDHC card (always at the mercy of the PIC's memory).
My only gripe is the custom PCB layout. If it were widely available in mini-ITX format, then we would have less problems with finding a housing for it. I admired Illuwatar's mini-ITX design, but there don't seem to be further developments from his side...
Cheers
Edwin