From what I've heard in the past and from doing a little reading, Guinness is brewed in 50 different countries which, for my money, would account for some of the variety in taste worldwide. However, according to www.guinness.com the beer served in the U.S. comes from "the brewery headquarters in Dublin".

Having sampled Coors Original all over the country I can say that there is a distinct difference in taste depending on where you are located. Also, the further you get from Golden the more the quality tends to deteriorate. Perhaps this is the same effect that is being seen with Guinness. Just another theory

Also, for fellow AZ FTs, my 110 degree beer is Tecate with a lime and a pinch of salt. Man am I glad summer is back.