These charts represent the major components of the Journal of Commerce Index of commodity prices (top chart is the entire index). As should be obvious, there has been significant price appreciation over the years in all commodity prices. I've indexed all the charts so that they are equal to 100 in early Nov. 2001, which was the bottom for an overwhelming number of commodity prices. Gains since then range from 80% for miscellaneous commodities to 400% for petroleum prices. (My thesis has long been that this low in commodity prices was in large part the result of very tight Fed policy from 1995 through 2000.)
When so many commodities (the majority of which do not have futures contracts tied to them) rise by so much over the same period, I think it is logical to assume there is a common denominator or two at work behind the scenes. The prime suspects would be a) accommodative monetary policy and b) global growth. And the implications for investors is also straightforward: there is no reason to worry about a double-dip recession or deflation.