My comparisons (physical comparison) for 2009 were the Cowon S9 (after a year of owning mine)
Samsung P3 (spiffier default GUI than S9, but afaik, about the same sound, has a sort of cheap plasticy feel instead of a nice sturdy feel like the S9)
and the Sony NWZX1060B/1050B (In real life, the granite feel is actually cool and spiffy. Great GUI, and the sound is amazing. Gives the Cowon BBE a run for its money, but damn money runs fast. Overpriced as hell, but damn it's nice. I like the GUI better than Apple products and it far exceeds that of S9 and P3 in that area as well. Sound far exceeds that of iPods. But file support afaik is about the same as the iPods but for sure superior to that of the iPods. Touch screen as well, but the GUI isn't as clunky as the iTouch) This directly fights against he iTouch and even though Cnet makes fun of the smaller screen, this pmp easily defeatsthe iTouch imo since it's actually a pmp and not a media player like the iTouch.
I really hope to get a hands on for the i9. That one interests me for playback in a car. It has its own built in speaker so thus using an aux cable and whatnot and taking up the headphone jack. It also has the right amount of GUI etc to not really be something I'd feel bad leaving in a car and not having as a main pmp(Like my S9). Price is also right as well.
There's another pmp thread that compares pmps. It's a few months old, but many of the discussions are still valid.