[Bartweiss]

To me it's a particularly intriguing move because Cortana's story wasn't a happy one. I know that most of the people aware of that fact also won't be fazed by it (if you've played that much Halo, you can probably distinguish the assistant from the character), but it's a surprisingly deep choice to take a name from a character who faced AI decay and all kinds of other scary techno-ills.