Big - We're talking GIGApixels of data (3.7 gigpixels in this image thumbnailed here)
Wide - Wide enough - like 150 degrees - that presenting the "right" projection of part of the image is non-trivial
Deep - So deep that high dynamic range comes into play - over 100x variation - as you zoom and pan around.

Is this a single image of a skyline... or a photo of a crane operator?

How do you capture images with these qualities?
 and then
How do you view them when you've got 'em? 

When I was in Seattle for TechReady, I attended a cool talk from Microsoft Research given by Michael Cohen and Matt Uyttendaele from the Interactive Visual Media group, where they discussed new techniques for capturing multi-gigapixel (big), panoramic (wide), high dynamic range (deep) images.

As part of Microsoft Research Techfest event, they released a public demo of their HD View technique.

Unfortunately, Internet lag (from here in Ireland anyway) diminishes some of the whooooooa effect you get while exploring these images, but it's still really cool.

Check out the site to learn how MSR is tackling these challenges with HD View.  And see if you can find the owl in the above 3.7 gigapixel image.