i can't see how the pope have a big impact nowaday.
McCain is just a candidate, he hasn't done much yet to have a worlwide influence.
Look how society transformed with printing's invention, art distribution is something quite important. the whole web 2.0 is a huge change in the world of communication, and Radiohead is arguably the artist who best used it, surely best exposed the possibility of this new reality. this is to me, much more important than the less interresting presidential campaign of a single country.
there is some flaws in the list (i personnaly hate lists), but it's sad to say that artist, entertainers, sportsmen don't have impact in our lives. they do, not in the same way politicans and businessmen does, but they surely do have an impact. People who push the limits of such things as writing or playing football are to be remembered as much as politicians.
as much as i adore the guy, i just don't like the inclusion of Colbert, who have limited impact outside of north america. they should make an american list and worlwide list, since they are an american mag.
EDIT: oh ok, he wasn't on the writer's list, well say, Oprah instead.