Good news, everyone! I finally got my hands on a Zoom H4n demo unit. I'll be putting it through the paces over the next few days and I hope to determine how it stacks up against similar machines like the original Samson Zoom H4 and the somewhat more costly Sony PCM-D50.
Keep in mind, my background is as a radio producer. I'm not a nature recordist, a bootlegger, or a musician (at least not a very good one). So my primary interest is in finding a computer that does a good job of recording vocals and ambient sound in a variety of settings using a variety of inputs including dynamic and condenser microphones and the built in mics. So my review's not going to be definitive, but hopefully I'll be able to tell you within a few days whether I can recommend this recorder over others that I've tried.
In the meantime, you can check out this unboxing video I shot this afternoon.