In 10.7, if you Option click the bluetooth menubar icon, you get the bt version, name and MAC address.

If you then highlight the connected device, you get the information listed in this hint as well as Role, Address & Battery Level. Or at least you do with my Magic mouse.

This works in 10.6.8 also!

The menubar feature is also available in 10.6.8!

I love this. Now I can see my readings and confirm that keyboard and trackpad performance is pretty weak at twenty feet.

I am getting -72 Trackpad and -79 Keyboard numbers.

I noticed something particular. For most icons you need to hold-down alt and then click, but for TimeMachine you can press down alt after you clicked, this does not work in the other menu's I tried (like: Airport)

Try selecting the Perform Tasks button next to the - + buttons and select monitor RSSI. A window pops up with a graph displaying signal strength for the selected device. This will stay on screen as long as the prefferences app is running. Only tried this in Lion but I'm hoping this will help me find out why the trackpad becomes unresponsive and "jerky" at times.

I've seen exactly the same behavior with my Magic Trackpad under 10.7. For me, every few hours it'll get very jerky. Resetting it works, as does waiting a minute or two.

Using the regular trackpad on my MBP, I was able to get to System Prefs and see that the Bluetooth signal strength was *not* the issue. Strength of -59 was right where it is when it's working normally.

Looks as though this trackpad issue may have more than one cause. My trackpad worked fine in Snow Leopard but suddenly started to lag, skip and jerk at times. This may have started after an OSX update as reported by many others in various forums, but I can't be sure. This problem has continued in Lion. However when the trackpad plays up I found that moving it a couple of inches resolved the problem for a while. This got me looking into signal strength and indeed I found that my BT signal is way down around the -76dBm to -80dBm level much of the time. If I slide the trackpad closer to my MacPro it performs OK immediatly and the signal rises dramatically. When pulled further away the signal drops and the jerkiness returns. I intend trying an external bluetooth antenna to resolve this. I have seen this solution elsewhere for a similar issue with the magic mouse, so fingers crossed.

Well folks, thanks for the tip's re bluetooth signal strength. It's helped me to sort out my trackpad unresponsiveness. I have followed the tip at http://www.mcelhearn.com/2007/04/19/apple-bungles-bluetooth-in-mac-pro/ (read all the comments before trying this), and bingo my BT signal strength has rocketed by 30dBm or more and the trackpad so far is as smooth as silk. I'm not 100% certain that this is an error on the part of Apple as the article suggests but it does seem to swap the BT signal to an aerial which is at the front of the mac-pro case rather than underneath. For me the effect is to put the antenna much nearer to my trackpad as the mac pro is under my desk. My airport signal also seems unaffected but as I don't use the mac-pro for wireless I can't be sure that its as strong for wifi connections as it was. Ill post a further comment when I have used the trackpad for a while just to be sure.