I just read a rant from Real Simple magazine about canned pumpkin. The gist being that it isn't really pumpkin after all but a variety of squashes!!
Actually I couldn't care a bit. I tried making pumpkin for pie one year from my son's Halloween pumpkin. Boy was the flesh very very wet and it took forever to cook down and still wasn't very pumpkin-y.
I'd rather open a can of so-called pumpkin and know that the consistency and flavor will be what I expect it to be and will make my pumpkin pie..cookies or whatever right!! And the US gov't agrees with me and has very loose pumpkin regulations.