Wow, I think this is one of the most useful additions to this conversation in days.Called 'em out. I wonder why they did it; seems so arbitrary without a concession or replacement.
That's the real question isn't it - why?
And while others may dismiss it as idle speculation, i think it an ideal question to grapple with on the MacRumors forum.
My speculative answer, given what facts we know, is this: There were several factors influencing Apples decision to drop Firewire on the MacBook. This fall into the basic categories of expense, upsell, obsolescence and precedent. There were most probably design issues with putting Firewire into the new case. These could almost certainly have been overcome, but only after more expense and time in the design phase. Faced with this, other advantages of ditching Firewire will have become more apparent: the cost of the chipset and the licensing(?), and the fact that Firewire needs to be able to draw a lot more current than USB2, probably necessitating a more pricey power supply. Add to the the upsell factor - MacBook Pros are suddenly differentiated by having Firewire, possible increasing sales of the high end machines, (obviously banking on people staying with Macs and not switching). Also add to this Apple's desire to do with Firewire 400 altogether. This is not because Firewire per se is obsolete or no longer in demand, but rather, it's been superseded by Firewire 800, which is fully backward compatible. Firewire 400 is also known to suffer from a design flaw (not present in FW800) which causes ports to blow. If this happens when machines are under warrantee, it's a further expense to Apple, so another incentive to get rid of it. Finally the MacBook Air factor - the MBA has been Apple's single most profitable computer line in the last year, and it's set the precedent of being the first Mac for years not to have firewire. Presumably, the huge success of a computer without Firewire has persuaded Apple that dropping it from another laptop line wouldn't necessarily cause too many problems.
Altogether then, a compelling business argument for getting rid of Firewire on the Macbook.
Having said all this, I would still argue that this decision was a strategic blunder for Apple. It might not be such a bad thing for their bottom line in the short run, but that's hardly an issue for them at the moment. What's much more in question is whether they can continue their recent successes in the medium and long term. Firstly it's a terrible way to treat customers. To bring out a new product line having removed a major piece of functionality, without replacing it or providing any work around, is guaranteed to inconvenience or enrage a lot of people. The argument that it's somehow not needed anymore is clearly nonsense, and not an explanation anyone whose invested in Firewire devices is likely to accept.
Using firewire to leverage upselling (to the MacBook Pro) is also unwise. It may work in some instances, but it's shooting themselves in the foot, as it harms Firewire as a standard. Not only are there less machines supporting it, and therefore, less people developing for it, but this lack of commitment or clarity over Firewire, will only serve to persuade both users and third party developers that the future of the standard is uncertain, making it's gradual demise all the more likely.
With regard to obsolescence, it does indeed make sense to get rid of Firewire 400 in favour of 800, or better still S3200. What surprises me is that this was not done long ago. Symptomatic of Apple general confusion when it comes to strategic thinking, I think. Had they grasped the nettle long ago, and fully switched to FW800, there would be massively more support for FW800 everywhere else too.
The MBA argument may also turn out to be spurious - although Apple has been able to rely on high-end consumers to buoy it's sales, counting on this at the expense of it's more traditional base could be a very risky strategy, both in terms of the current "credit cruch" and its effects, but also because Apple relies heavily on creative users for the identity of the Mac computing platform. Also let's not forget that the MBA was designed a super lightweight laptop with functionality deliberately reduced in favour of portability. Hardly a template for future computer design across the board.
Finally, Firewire has been very much in keeping with Apple's focus on good design over the years. Within computing, there's been a general move towards dedicated subsystems for data-intensive tasks: dedicated graphics cards, network adapters, IDE / SCSI / SATA buses for storage etc etc. There's good reason for this - it frees the main system up for more of what you want it to do and a subsystem will generally perform the task far better. Firewire, with its own bus, is very much in keeping with this approach, and as such has proven itself to be outstandingly well suited for a great many tasks. It would be a great shame if Apple, who invented it and nurtured it, and who have contributed so much to it's ongoing development, suddenly failed to have the vision to support it any more.
Sorry, long-winded i know, but i've been thinking about this, and i wanted to share