Eh, neither series has much that's original in it. Warcraft/Warhammer took everything from Tolkien and early Tolkien-inspired fantasy. Everything in Starcraft and 40k is taken from guys like Heinlein, Geiger, etc

And really Starcaft vs 40k is especially silly because they both did a lot of copying from each other; In 3rd edition, GW took the Tyranids and basically eliminated all major aesthetic differences from the Zerg and turned them into a MUCH closer copy of zerg, than zerg were of 2nd edition Nids.

The whole thing is kinda silly because those entire genres were inspired by a small group of people, and pretty much every concept is "stolen"