The offical way is to send your camera in to Canon service and they'll tell you. There is no menu, etc. that you can view on your own to get this information directly on the camera nor with any of the Canon supplied utilties.
However, there are some third parties that have written utilities.
Dire Studio has a utility called "Shutter Count" (be careful because "shutter count" is a common name and there are lots of things that don't actually work.) You can get it from their website (or from the Mac "App Store" if you own a Mac). It's pretty cheap (less than $5). These utilities don't necessarily work on every camera model, but the 50D shows up on their list of one that they've tested and certified as working.
Tim Campbell
5D III, 5D IV, 60Da
