Those of you using Linux should give the latest Digikam a try. In conjunction with its photo editor, showFoto (supports 16 bit per channel), it is now taking care of 99% of my photography software needs. Digikam is miles ahead of Picasa. I haven't tried Pentax Photo Browser, but I would doubt it to be any better than Digikam.
http://temporaryland.wordpress.com/2...-comes-of-age/