Halo took INSPIRATION from works like Ringworld, Aliens, and many more sources. Destiny is doing the exact same thing. There's nothing wrong with adapting other people's ideas so long as you put your own unique spin on it. If people didn't "rip off" others in the video game industry, there would not be that many games. One company would make a turn-based strategy for example and then NO ONE ELSE COULD MAKE A TURN-BASED STRATEGY BECAUSE SOMEONE ALREADY DID THAT OH TEH NOSE. I think Destiny is looking like a well-polished game taking inspiration from Bungie's Halo experience, Borderlands, and countless other games. I'm excited to see how the game comes together.