Update 6/13/11 (a few thousand miles later) - After reading some horror stories on accessnorton.com about this exploding - I got nervous about failures. I removed it and went back to the stock setup. I'm hoping to try Jim Comstocks latest creatation - a hydraulic tensioner. I have to admit that running this seemed to smooth the engine out a bit, noticabaly. I'm guessing it's due to the cam chain tension changing when the lifters hit the back sides of the lobes which affects the timing. It made the upgrade seem worth doing. 

RMA Automatic Cam Chain Tensioner

The RMA tensioner is a pretty nice upgrade in that it takes up most of the slop that occurs when the cam lobes are pushed around by the valve springs. By taking up this lash, the ignition timing is much more stable, and I think the bike runs a lot better. Other benefits include no maintenance, quieter timing chest, and potentially less wear on the cam chain due to the preload. 

Here are the parts (you reuse one of the original plates). These parts have been in my bike for around 5000 miles and frankly look pretty good. 

For more info and how to install see http://sites.google.com/site/rmaengineering/

There seems to be some concern about the quality of this part - a few folks posted examples of catastrophic failure of the part 

http://www.accessnorton.com/broken-rma-adjuster-t6242.html

http://www.accessnorton.com/rma-cam-chain-tensioner-t5491.html

If you look closely at the pics of the failed part, it's in about the same place. In looking at my part, i can see two marks that were apparently stamped into the metal as part of the metal forming operation.

It's my uneducated guess - but these marks could be inducing localized stress increases and under load, cause the part to break. It also seems the failures noted where in engines that were modified for performance - i.e. taller cam lobes. I'm wondering if the added tension in the cam chain to run taller lobes along with higher revs pushes this part beyond its limit. Others claim to have over 10,000 trouble free miles, but I'm guessing they are closer to stock engines.  

I've decided to reinstall it and hope for the best. I'm no radical rider, so hopefully it will last.

Here's a pic of the installed unit