What Gutenberg invented was metal movable type which was both cheap and high quality - a new casting process combined with new metallurgy. Those innovations combined with an alphabet turned printing into a mass-market success and a turning point in world events. It'd be good if the history books (etc) presented Gutenberg's work for what it was: not the first printing press, not the first movable type, not even the first metal movable type - but the first combination of all three which was (relatively) cheap and high quality - that being what made it significant. Oh yeah, and being invented at just the right time and place to find a mass market waiting for it - or, to put it another way, being invented by someone who spotted the mass market waiting (who then got ripped off by the man providing the funding - look it up...)