True, but this wasn't the doing of Conde Nast, nor did Conde Nast see this 10x increase when they pushed reddit out on its own. Reddit's growth was organic.
Last I heard, CN still owns reddit even though the site now operates independently, so CN still has the chance to recoup their investment, but this will take a more profitable business model without sacrificing user trust. Valuations on sheer page hits or user counts are faulty with a capital F U if you can't figure out how to make money from them.
It doesn't matter if it was Conde Nast's doing. They made an investment in a new media property, and it has seemingly gone splendidly with little to no 'fallout' from having a corporate overlord owning a community site.