I just spent 1.5 hours typing this for another thread so I might as well post some excerpts here cause it is just so relevant:
As for multi-touch on existing platforms - my feeling is that its entirely feasible that in either 10.5.2 or a later firmware upgrade for keyboards/trackpads will introduce this technology beyond the Air. I believe this because my trackpad knows when I am using one finger, and it knows when I am using two fingers. It also knows when I am using more than two fingers, because it does not respond.
It makes sense for Apple to use Macworld, Macbook Air, and iTouch to debut the new technology. But if multi-touch is available for those two entirely different hardware, why not other touch-pads?
The flipside of the coin however comes from the fact that the upgrade for the iTouch is not free. This is an interesting precedent for Apple, and only time will tell whether or not Apple will continue down this road. I am curious how the availability of an upgrade for iTouch users was communicated for those who are not in the know. I suppose that when devices were synced following the release of the upgrade, users were automatically taken to a page on the iTunes store announcing new features and requesting $20. Insight here is appreciated.
So if Apple is charging for that software, why not charge users for the ability to use multi-touch? From a business standpoint it seems rather lucrative.
Or perhaps lets say the multi-touch is hardware dependent. Hypothetically, Apple could have silently started including a more advanced touch-pad at any point over the last year without any of us being the wiser. Just because the Air leaked out of Apple's balloon doesn't mean they can't still keep some secrets. I will use myself as an example: I bought my macbook in November shortly after the hardware upgrade. Unless you are an electrical engineer who took apart two different laptops and closely examined the touchpad for some change which a layman like me could not identify, how would you know if it was any different? I do suppose an Apple Genius might notice, but then again they probably haven't had a chance to look at too many newer macbooks yet. Anyhow, if this is the case than you pro users are screwed - so I discount this theory, but its a fun one.
My last argument for multi-touch on existing platforms would be the ambiguity of the wording that Apple has been using since Tuesday about it.
As for the upgrades, the 10.5.2 release - I peg it to be between Noon Wednesday 1/23 and Noon Thursday 1/24 PST, without multi-touch (just a WAG). I do see it being available, but only after Air has been available for long enough for the die-hards to go pick it up in retail. Lets say beginning of March - but I bet its ready now (that we may never know).
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