A nice FedEx man rang my doorbell today and dropped of my brand new Sony PCM-D50 digital audio recorder. I won't be able to post a thorough review for another day or two, but here are some photos in the meantime.
Oh yeah, and I also couldn't resist giving the recorder a quick sound check. Keep in mind, I haven't read through the instruction manual yet, and I haven't tinkered with the settings very much. But my first impression is that while the internal mics have just about the same level of hiss as the mics on the Zoom H4, you get a much more natural sounding vocal tone with the PCM-D50.
You also do need to hold the PCM-D50 carefully when using the built-in mics. While you don't get as much handling noise as with the Zoom H4, you'll definitely notice some noise if you change your grip.
But the most impressive thing, and the reason I bought this recorder in the first place (aside from good hardware controls, a great limiter, a sturdy body, and 4GB internal memory), is that it sounds great with a dynamic microphone. Grab a good pair of headphones and listen for yourself.