Ebows are way way cool. I love them. I have used both versions (1st and 2nd) and I like the second one better. The second edition has two modes, harmonic and regular. The harmonic gives lots of overtones and harmonics (duh).

Anyway, the ebows are great for feedback sounds. Collective Soul uses them on Run and if you are play 'Angels of the Silences' by Counting Crows, the first note is much easier to do with an ebow.
I use an ebow a lot. I like them on 'Buckers and ASATs. Especially ASATs. They sound great. I am not so fond of the single coil ebow sound. (ASATs have pattented pickups that aren't quite the same as single coils).
I use ebows with Slides for some amazing accopanyments. (sp?).. They can sound hypnotic and string like, as well as raunchy and loud with the gain up. When tracking I usually use a volume pedal as suggested by Mr. He. When playing live, I just play with the sucker.
The real challange of an ebow is making it sound good on acoustic guitars. I love it when they are properly used on them. Of course, it is much easier if you have some sort of soundhole pickup, like a Fishman Rare Earth or something better. The dean Markley pro-mags don't cut it. I have seen a guy, who plays solo and with an acoustic guitar, use an ebow like a god. If you are interested in the best acoustic music known to man, chek out
www.michaelkelsey.com
he plays a mean ebow.
Anyway, I guess I have rambled enough...as usual.
MIKE