said by Mr Matt 
: 
What better way for the wireless network industry to weasel the consumer into replacing their hardware every six months. By not having a final standard for 802.11n and changing the preliminary standards on a regular basis one must replace their hardware regularly in order to have the fastest throughput. Last months N client may not work with next months N access point.
That depends on if the device needs an upgraded/replacement chip or if the use of a microcode flash will do the upgrade to the standard. So long as you can just use a microcode upload (as you can for your router) the device can be easily made compatible with the updated/revised standard as it evolves.
