Do you need Wifi? Price range, etc? My sisters and I each chipped in and we bought
this Samsung SPF-85v for my parents. The great thing about having the Wifi is that the frame automatically updates pictures from different RSS feeds. My sisters and I, for example, have created albums using iPhoto and MobileMe and Google's Picasa. These are uploaded onto the web and download directly into the frame. Plus, the frame has its own email address so you can send pictures to it from a cell phone or any location while you're traveling.
Most frames have an aspect ratio of 16:9 which can be annoying for many people since most digital cameras use a 4:3 ratio.