Nope, not Time's 100 best books since 1923. ASME's Top 40 Magazine Covers of the Past 40 Years. It's a pretty good list.
My biggest quarrel with these sort of lists is that they should not consider anything recent: we're too close to have perspective. Only once the century/decade is long gone can we really assess the "best" or "worst" or "biggest". The same with the above: what about the Top Magazine Covers from 1965 - 1995? Yes, some of the more recent ones will have staying power and be considered important or classics. But some won't, so it's silly to presume that we know today what will be a classic in the future.