I doubt you would be able to upgrade the card, but apple or some 3rd party would probably offer a usb wi-fi card supporting the new standard once it is approved. If you are like me, my iMac is just feet away from my HDTV. I'll probably just use an ethernet cable to connect the imac to the iTV once it is released. If the iTV supports gigabit ethernet, then it will be much faster than even the 'N' standard.
You may be waiting until MWSF08. 802.11n is not due to go to Final Approval until Jul 07. I can't see Apple releasing pre-n Airport.
Are you sure 802.11g can't stream video. I've sat upstairs at home pushing a DVD off the iMac G4 up to my Powerbook G4 (with dead optical drive) it stuttered quite badly; but that was over Airport (11Mbps). So my guess is 11g might handle it anyhow.
The other factor is that Disney have leaked that 'iTV' may well have it's own harddrive.
Well if WinXP is reporting this correctly I'll have to eat my words; having read the same story on TUAW yesterday.
I would say that Apple has a history of crippling hardware though; so even if it is in there, it doesn't mean we get to use it:
- DVD-RW drives limited to DVD-R media only
- Graphics cards only mirror displays
- One of two processor cores present disabled in a 'Single' core machine.
Today's Macs (i.e. since the Intel switch) have 802.11a hardware - but again we can't use it.)
I would suspect that IF apple provided a N card, it is only because they forsee having to use it in the future. Since it is not a approved standard yet and because they don't have a N standard basestation yet and because iTV is not released yet, I can see them temporarily blocking the N functionality. but when they release iTV next year and can all of the suddenly say that their core 2 duo (maybe even the core duo) computers already support it, it will be a feather in their cap.