I think both the Gutenburg Press and electricity both have equal weight in their importance.
The electron, as we all know for being the medium through which electricity is transported, opened up science like a Christmas present. From there we discovered quantum mechanics and theory, thermodynamics, chemistry advanced like it never could without atomic study. Not to mention electricity being the forerunner to the entire electronics industry that supplies us with equipment we use daily - tools that have made our lives far more efficient than just a few decades ago.
But the Gutenberg Press is of equal importance to the process of this science. Word would get around, published papers exclusive only to those with the money to afford the scribe's time. In a sense, physics of the past would have been a very eclectic field with people paying extortionate amounts for the few texts that would be scribed.
I don't undervalue the atom, or electricity, on the purpose of necessity but yes, science needed an efficient way of printing their results and findings to the masses and the Press did just that.
EDIT: Sorry, I should clarify since the electron wasn't "invented" but the mediums of transporting and regulating it are.