It seems like there is a need in the market for some type of multiple SPDIF to firewire device. That way people with two or more converters could get the audio recorded into a mac or windows laptop via firewire.
The MOTU Traveler might be able to do this. If the AES and SPDIF inputs are both independent and can be active at the same time.
I am thinking more in terms of a utility box with two SPDIF's (or more), firewire, and a driver for OSX and windows that captures the audio.