The most basic display in playback mode shows the file number and image quality setting briefly for each frame. Pressing the DISP button adds further information; file size and exposure / white balance / ISO settings (as shown).
Pressing the DISP button again changes the display to show a histogram.
The left zoom button switches to a thumbnail display.
Unusually you can choose between 2x2, 3x3, 4x4 or 5x5 thumbnails.
You can also browse images by date using this 'calendar' view... not sure how useful this is unless you never empty your memory card.
The right zoom button magnifies the image in seven steps, up to 10.0x.
The playback menu has four tabs - play, edit, card and 'album entry'. The four directional keys on the four-way controller are used to select each option.
The edit menu has a range of sophisticated options that would put most much more expensive cameras to shame, including color conversions, brightness and saturation adjustments, cropping, red-eye removal, fancy frames, adding text and even the ability to produce multi-image layouts and calendar pages in-camera. Very impressive and great fun, if of limited value to more advanced users.
Something very rare in cameras of this type is the ability to edit the settings used in raw files after they've been saved, and save the result into a new JPEG file. You can change white balance, sharpness, contrast and saturation, and choose from any of the standard file size / quality settings.
When editing raw data the result of the changes you make is reflected in the on-screen preview. Very neat.
The SP-500UZ offers a fairly sophisticated way of organizing the images on your xD card into 'albums', complete with natty ring-bound frame effects. How useful this is will depend on how long you intend to keep the images on the card I guess.