@Jumpship:
[opinion/educated guess]
;-) I suspect "underwrite" means that Eyetech will be supporting the trade-in policy financially. That is, you take your old G3 board to your local dealer to trade it in on your new G4, and your dealer sends it on to Eyetech if no one in your area is buying the old boards. This way your local dealer isn't forced to buy back boards he cannot sell. Or something. Maybe.
[/opinion/educated guess]
:-D Still, looks good!