This thing looks sweeeeeeet.
As for the Feiten system, it's not strictly based on piano tuning, even if that's what his literature leads you to believe (dunno, haven't looked at his literature in a while). It is based on a combination of 2 things, one of which is guitar-specific. The guitar-specific thing is that when you physically press down on a string, you pull it sharp. A compensated bridge partially makes up for it, but until Feiten popularized it, there were very few people doing compensation at the nut (though it WAS done before he was even born), which would complete the equation.
Feiten takes it one step further by having meticulously calculated the amount of compensation required as you move from different guages of strings. Your guitar that's "Feitenized" with .10 at the high E string won't be perfectly compensated if you decide to switch to .11s. It WILL still help a bit, though, since there are certain factors that are pretty much universal (ie. that the G string usually requires the most compensation).
The other factor that can be related to piano tuning is the idea of tempering. As piano tuners know, a fully-completely "mathmatical" tuning using strict numerical relationships of the notes to one another rarely sounds 'correct' (and especially, doesn't sound 'pleasing') to the human ear. Other instruments have used tempered tunings for as long or longer than the piano, but of course the piano is the most well-known and significant example of tempered tuning in action.
Just blabbing...
This Strobe Tuner still looks awesome. The one Bluedad linked to looks even better, but a grand is out of my price range as a person who's not a piano tuner.
Besides that, the guitar is an imperfect beast at best and that sort of precision won't get you much further than the Peterson will. Unless you get Steinberg or LSR 40:1 gear ratio tuners, you'd be hard-pressed to physically get your guitar that accurately to pitch; and with guitar strings being not only elastic, but prone to other changes (aging and corrosion from sweat will make your string more difficult to keep at one tuning) it wouldn't last longer than your first chord and solo anyhow. Greg
