It's easy to use, indeed.
The problem is that I need to see ALL EXIF data from my DSLR, and this tool won't show everything. GraphicConverter's "exiftool" shows much more info, for instance. So, while's it a neat little app, it's not the right one for me, sadly.
As of 2/2010 EXIF Viewer is up to 2.7 for Leopard and 2.7.1 for Snow Leopard, but MacUpdate is only listing version 2.6.
This is an okay EXIF viewer app, but does not grab EXIF data as well as Xee, which is also an image viewer. For example, Xee is able to find EXIF data from pics on eliotshepard.com that EXIF Viewer cannot.
Really good application and very fast. Display all fields and not only basic ones like other apps.
A must have if you need to look at exif data quickly.
One more feature will be to have the option to display or not the pictures.