Does the Firmware upgrade require our cards to be sent back to you?
Yes, as it is not feasible to have a JTAG chip programming operation being done by users. You need a special programming dongle, a suitable cable and a PeeCee for this.
Also, does it only fix the DMA, or are there any other goodies we should know about?
Prometheus supports PCI-PCI DMA in all four PCI slots, with fairness arbitration (no special ordering for PCI cards necessary) and high speed interleaving between PCI and Zorro accesses. Also supported are PCI-PCI bridges as being used on Multi-IO PCI cards (like ethernet + USB2 + Firewire / ATAPI cards) and modern PCI VGA cards, so you can save some PCI slots with ethernet and USB on one PCI card.
There are also quite some internal changes in the firmware which you won't see as user.
Michael