Man, what the FUCK kind of camera can take a picture that huge? Shit, im amazed, and also, it really does look like a normal earth desert doesnt it 
well all those mars nasa images are panoramic composites of multiple images (I just checked wikipedia, and it seems the rover has 4 cameras that take "a panoramic mosaic of four pancam images high by three wide")
edit: that was just an example for one certain photograph. Either way, there are 3 cameras taking multiple photos and then compositing them together (probably back on earth)
edit2: I think what's more interesting is that NASA has huge TIFF versions of these photographs available for public download that are over 400MB's! Imagine all that data being sent through space via satellites...... from a planet MILLIONS of miles away.
I want that net connection......