A reader tells me that a flap is being raised over Apple's newly released $1.99 802.11n Enabler for Core 2 Duo Macs. There's some wild nonsense flying around, so let's nail down the facts.
You may not have an 802.11n-equipped Mac. Only Core 2 Duo MacBook, MacBook Pro, iMac (except 17-inch, 1.83 GHz) and Mac Pro (with the wireless option installed) support 802.11n in hardware. All other Intel Macs with Wi-Fi have 802.11a/b/g networking. PowerPC Macs have 802.11b/g.
802.11n cannot be added to Macs that don't have it. Bummer. There's always USB and ExpressCard, so don't lose hope.
If you buy a new AirPort Extreme, you get an unlimited site license for the 802.11n Mac client enabler for free. Contrary to other reports, the enabler that comes with the AirPort Extreme CD can be used on any number of Macs at the owner's site. The AirPort Extreme CD has a redistributable package containing the enabler. I did the full software install on the MacBook Pro and verified that it enabled 802.11n networking. I copied only the Enabler package file to a MacBook, installed it, and found that it had enabled 802.11n. I wasn't required to associate with the AirPort Extreme to get 802.11n going.
If you don't have any draft 802.11n equipment now, keep your $1.99. The enabler adds absolutely nothing to a qualifying Mac other than to enable 802.11n. The enabler will not speed up or otherwise enhance 802.11a, b or g. I believe that 802.11n will be bundled with Leopard. Can you wait until June?
After you run the enabler once, it sticks to your Mac forever. You will never have to buy the enabler again. Roam from one network to another network and your Mac's n-ness will remain. You can wipe your Mac clean and reinstall OS X from scratch, and your machine will remain n-enabled. If you replace your whole Mac, run the original enabler again on the new machine and you're covered.
Apple is required to charge you for the enabler. 802.11n was R & D intensive; it's not your granny's WiFi. You can't amortize R & D costs against new products--in this case, AirPort Extreme and Apple TV--and then give that same R & D away somewhere else. That would create what's called an accounting irregularity, and these aren't popular at places like Apple and Dell just now. The only way to put 802.11n into existing Mac users' hands was to turn it into a product against which R & D could be charged. $1.99 is a token, the very least that Apple could charge you and still call the enabler a product. If Apple hadn't come up with this sound solution, you'd have to buy AirPort Extreme--an extraordinary product, as you'll read in my review--or wait for Leopard in order to get 802.11n.
Nobody can promise that the 802.11n draft will match the final specification. Chipmakers claim that they can adapt to changes in the spec with firmware updates. If no one else planned for that contingency, Apple did. It releases plenty of AirPort compatibility updates as it is. Apple's network team is on it.