Noted security expert Steve Gibson was on Lab with Leo (Leo Laporte's TV show which airs in Canada and Australia) this week discussing Bluetooth security, or lack thereof.

He warned about sniffing during pairing, discovering MAC addresses, transmitting malware, and transferring files from Bluetooth enabled devices without knowledge or consent of the owner.

His basic recommendations were:

1) If you're not using BT, turn the BT radio off.

2) If BT is on, set discoverable devices to "hidden"

3) Never accept any unexpected prompts from a BT device.

4) Check for updates in case your device manufacturer has updated to newer and more secure profiles (which may be coming in the future).

Full transcript:

(Gibson begins on page 66)

Gibson has also discussed security for Bluetooth keyboards in the past (in terms of sniffing data) but hasn't found (or at least passed on) any hard data for that yet.