How secure is Apple's Bluetooth keyboard?

Solution 1:

The simple answer is "it's secure enough." The Apple Wireless Keyboard uses bluetooth, which since 2007 has been quite secure.

The pairing process protects you in a number of ways, as outlined on wikipedia. While wireless connections are always subject to sniffing, bluetooth uses public-key cryptography to securely exchange the keys used to encrypt everything else between the keyboard and your computer. Also, your computer will make you enter a code on the keyboard during pairing—this is done to protect against a man-in-the-middle attack.

The Wikipedia article on Bluetooth has an almost obscene amount of relevant information.

Basically: get the wired keyboard if you want a numpad. Get the wireless one otherwise. Only your computer will be able to see your keystrokes.