We've heard this from a couple of sources independently now, and we feel relatively confident about passing it along. Apparently Gamestop managers meeting for their annual conference have been told that the Wii Zapper will launch with pack-in game Zelda Crossbow Training. As Ars Technica's source told them, "The game looked beautiful. I'm pretty sure it was running on the Twilight Princess engine. It's a third-person game, and you had some control over Link."
The best part? Reportedly, the Wii gun will still retail for $20, which just promoted the Zapper from "likely purchase " to "foregone conclusion." Hopefully we'll hear official word from Nintendo on this soon.