Key Similarities:
Same radio (802.11b, embedded mini-PCI form factor)
Same software, including support for the award-winning Cisco Wireless Security Suite
Support for inline power
Plenum-ratable metal case
Key Differences:
The modular and upgradable platform of the Cisco Aironet 1200 Series has a mini-PCI slot to support IEEE 802.11b and a card bus slot to support 802.11a in the future. The Cisco Aironet 1200 Series Access Point features a new, integrated mounting system that enables the access point to be mounted on the wall, ceiling, desktop, and above the ceiling. The mounting system includes a mechanism by which the access point can be secured physically using the customer's choice of laptop security cables or standard padlocks. The new cast-aluminum case design of the Cisco Aironet 1200 Series provides the ruggedness
required in factories and warehouses, and now meets the aesthetic requirements of the corporate lobby.
http://www.cisco.com/en/US/products/hw/wireless/ps430/products_data_sheet09186a00800937a6.html
http://www.cisco.com/en/US/products/hw/wireless/ps458/products_data_sheet09186a008009247c.html