Andrew Soderberg said 7:55PM on 10-16-2008
While I lament the loss of FireWire from the new MacBooks (I was Apple's Original FireWire Evangelist from 1991-1993, while it was still code named ChefCat), I understand the reasoning. The BIG main advantage of FireWire over USB 2 is the isochronous (Same-Time) data handshaking/transfer. Guaranteed data delivery at the time it is needed. This is very important to professional video editors, needing to work with one or more realtime video streams. USB 2 just can't deliver that. While consumers benefit from FireWire in faster sustained data transfers than USB 2, they don't really take full advantage of FireWire's isochronous capability.
FireWire does cost more to implement in (chipset, connectors, licenses, etc.) than USB 2, and with everyone clamoring for lower cost MacBooks, something has to give. Also, you may remember the loss of Floppy disk drives, which Apple spearheaded, many a reporter claimed that the tipping point for no-floppy PCs had not come yet. When in fact it had, and Apple saw it and acted on it before everyone else.
Such is the way of FireWire on consumer products (computers and cameras).
Apple will not be removing FireWire from the MacBook Pros or the Mac Pro towers, as these are the workhorses for most media production houses. Until such time as some other much faster peripheral interconnect comes to fruition, with the same or better realtime (isochronous) capability at a lower cost (there are faster interconnects - but much more expensive), FireWire is not going anywhere. FireWire also has 1600, 3200 modes coming down the pipe as well.
The impact for those of us semi-pro media/video editors, will be that FireWire based external drives may become more expensive as there will not be as large a market for them going forward.
As for Target Disk Mode, all Apple computers have had Gigabit Ethernet for several years now. Apple has made the new MacBook's Migration Assistant work with Ethernet. Gigabit Ethernet is not much slower than FireWire 400 (on sustained data transfers), so I suspect this also made the removal easier, since there is a reasonable alternative.