Is there an application that would allow some one to switch between two or more firewire
cameras using one computer?
Not for the Amiga. I'm sure an Avid/Premiere/Final Cut-equipped Mac or PC could do it.
The only "Amiga" Firewire interface was for the Draco and worked only with Movieshop. See
here.
There's no Amiga camera driver for any of the PCI Firewire boards, either. I think the most that's been done for PCI Firewire so far is a beta driver for Firewire hard drives.