So I made a new Redguard character on the Xbox 360 and when Alduin is supposed to land at the beginning, before you get killed, I see him just... flying. I hear him roar and he just soars overhead and roars and flies around. I waited about five minutes and he just kept flying, aimlessly, not sure what to do. I'm just wondering, did the latest update break the intro?

It isn't the latest patch. I only have 1.4 and he did that to me for a night. My suggestion is to turn off the system, reboot, and try again.

Well I've started about 4 new characters today (can't decide what type of character I want to play in Dawnguard ) and Alduin acted correctly in all 4. I'm on xbox as well

This has happened before the update, but it seems (don't quote me on this) that the update makes this more frequent.
It's listed http://www.uesp.net/wiki/Skyrim:Unbound on the UESP in the Bugs section. It says the only way to fix is to start over, not much else you can do.