I would be very surprised if anyone had managed to write and compile a Swift program successfully already they could use to compare seriously with anything written in Objective-C. This is the kind of thing that will take a lot more than a week.
Maybe next fall, at the iPhone event when iOS 8 goes live, Apple will have some carefully chosen data to share from a developer they've invited on stage. Most likely you won't get really useful information about this until months after that.