Re: How old is Thor?
Immortality in fiction often can have many different meanings. I take the Asgardians immortality to be very long lived/slow aging and very difficult(by human standards) to kill but not completely incapable of dying. Then you throw in the whole afterlife schtick with Valhalla and Hela and her realm and then even death doesn't mean the same thing for them as it does for humans. And that's not even talking about the Ragnarok/reset button.
2015 will not only see the MCU beat the HP franchise for the #1 WW spot but it will also see Marvel Studios pass Pixar in terms of WW grosses($8.585 billion). Marvel Studios/MCU avg. annual profit: $621m(there ain't none higher. HP was the closest runner up with $541m when it was active).