As far as I am aware the only way to find a 7Ds shutter actuations on a Mac is by installing GPhoto2 from source. Although this is relatively straight forward with a package manager, it is still rather involved for an average user and involves a 4GB plus download for Xcode. As a result I have put together a simple little app based on a GPhoto2 framework to do this.
You can get it here:
http://southwest16.com/use/shuttercounter-1.0.zip
Just connect the camera with the USB cable, open the app, and click the refresh button. It may take several seconds (just as when using the command line GPhoto2) so may beachball, but it will eventually show either the shutter count, serial, and name fields or an error.
The app should run on OS X 10.6 (Snow Leopard) or later, and I believe the shutter count is visible on the following models (or later in same range): 1000D (Rebel XS/Kiss F), 550D (Rebel T2i/Kiss X4), 50D, 7D, 5DII, 1DII.
I have tested it successfully with a 7D on Lion (10.7.5) and Mountain Lion (10.8.2), although you must quit the app before the camera disconnects (either sleeps, turned off, or physically unplugged) else the OS X USB controller will cause the program to crash.
Oct 15, 2013. Canon doesn’t have shutter count included on the EXIF information of an image file, as opposed to Nikon and Pentax. Read reviews, compare customer ratings, see screenshots and learn more about ShutterCount. Mac Os X Software Download on this page. Download ShutterCount for macOS 10.7 or later and enjoy it on your Mac. The original.
Canon Eos Shutter Count
Comments, bribes, criticism, bribes, irrelevant anecdotes, and bribes always welcome.
EXIF is available inside all my photos, though bribes are still recommended anyway.
You could visit my sparse South West 16 web site and rarely updated flickr stream...
...or you can check out my slightly more frequent London iPhone Twitter flickr. Sometimes in colour!