http://extension.usu.edu/foodstorage/htm/canned-goods/

This quote is from the Utah State University Extension Center.

"Commercially canned foods should retain their best quality until the expiration code date on the can. This date is usually 2-5 years from the manufacture date. High acid foods usually have a shorter shelf life than low acid foods. For emergency storage, commercially canned foods in metal or jars will remain safe to consume as long as the seal has not been broken."

The Canned Food Alliance also shares this view that canned foods are safe to eat as long as the can is not damaged in any way. They will lose nutritional value but are safe to eat. With this information, and the knowledge that most of the foods from the cannery will last 20 and 30 years, food storage and it's rotation have become much easier for everyone.