http://www.macnn.com/articles/12/12/17/patch.affects.recent.mac.updates/
Mac Wi-Fi Update 1.0 fixes problems with 5GHz Wi-Fi
updated 03:46 pm EST, Mon December 17, 2012
Patch affects recent Mac updates
Apple has posted Mac Wi-Fi Update 1.0, a patch for late 2012 Macs. The code fixes compatibility problems when operating on the 5GHz Wi-Fi band, 802.11n. The download is 1.49MB, and requires OS X 10.8.2 or later -- specifically, Apple notes, at least build 12C2034 of the OS.
Modern Wi-Fi typically supports 2.4 and 5GHz connections. The latter is mostly useful in cases where appliances might otherwise interfere with Wi-Fi, such as with a microwave. The use of 5GHz in the 802.11n standards is capable of transferring far more data, but also tends to have a shorter range when used exclusively compared to 802.11b and g's 2.4GHz frequency.
