2004 saw the introduction of 2 new Frontier units.
The Frontier 355 is the same as the 350, but with a new scanner unit, utilizing a 24-megapixel area CCD as opposed to a line-at-a-time CCD. This new CCD apparently paves the way for the "12-inch" Fuji Frontier, which is apparently the holy grail of Frontiers, since the Agfa d.labs and Noritsu (Kodak) QSS machines all do 12" paper, but not at the quality of the Frontier.
The real magic of the scanner unit is that it incorporates a dust-and-scratch removal algorithim, based on FARE technology present in Canon scanners. The more common ICE technology for this was co-opted by Noritsu, so it apparently wasn't an option. Dust and scratch removal in my mind is worth it's weight in gold. I run a 370 unit at my day job, and the environment is so dusty since it is an older building.
Apparently, the interface has been given a major rework, as well. You do not need a degree in Fujinese to operate it.
The Frontier 375 is the same as the 370, but with the same reworkings of the scanner unit that the 355 has received.
The hoary old PIC software is being redone. The Frontier Manager will be taking over from the PIC. I have little details on this at the moment, but this will supposedly support nifty things like ICC profiles and the like.
I'd like to say too, that the Fuji film developers are totally optional components to the Frontier system. As roller transport devices, they can and will damage film. The ideal solution today is to purchase a dip and dunk processor like a Refrema Olympic, which aside from weights on each end of the film, does not put the film through any physical contact with solid objects, ensuring a scratch free development (well, aside from any scratches from scuzz inside your camera...but that's the price of a film workflow...) process from start to finish. Of course, this is only a pro-lab option, since your average consumer isn't concerned about microscopic scratches on his or her film. And the Refrema machines cost as much as a Frontier...around $250,000 US dollars.