yes
The 2011 season will be the Steelers 79th season in Pittsburgh. The Steelers franchise began in 1933.
See related link to Pittsburgh Steelers official website.
They always have been in Pittsburgh, since 1933.
Because that is the team that signed them.
No, they have not. The Steelers were always an AFC based team, starting from 1933 when they were known as the Pittsburgh Pirates.