I had my first opportunity to try out my Fuji X-Pro1 with a Nikon lens (using a Novoflex adapter) last night at the Aimee Mann show in Wilmington. I originally bought the adapter because I wanted to use my Nikon 10.5mm fisheye with the X-Pro1, but I haven't had the opportunity to do so yet. Given that we had balcony seats, I took my Nikon 135mm DC f/2 lens (rather than the Fuji 60mm that I used at the David Bromberg Quartet show last month) for the extra reach and large aperture. The downside to this lens, at least when attached to the Fuji, is that it's manual focus only. I was worried that it would be hard to get images that were in focus, but it ended up being okay. Sure, it's not as easy to manually focus as with my FM3A, but it's certainly more than useable. I hit focus about half the time, which doesn't seem to be so bad given the circumstances (i.e., long lens, large aperture, moving target, handheld from my seat). While it's certainly a bulkier lens than you'd usually want to use regularly on a small-bodied camera like the X-Pro1, it wasn't too unwieldy.
This has me thinking more about the just-announced 55-200mm Fuji zoom. I wonder how it would have autofocused in these conditions (especially in the low light)? At 200mm it's 2.5 stops slower than my 135mm, but with stabalization it should be fine in reducing camera shake, although there would still be motion blur. If Fuji released a telephoto prime (somewhere between 135mm and 200mm) at f/2 or f/2.8, I'd be all over it as an awesome lens for concert photography.