X-Men ReLoad was the name given by Marvel Comics to their May 2004 revamp of the X-Men titles. The revamp was prompted by Grant Morrison's departure from New X-Men.
As a result of the revamp, Chris Claremont moved from writing X-Treme X-Men to writing Uncanny X-Men, with Alan Davis doing the art. Chuck Austen moved from writing Uncanny X-Men to New X-Men, which returned to its old name of simply X-Men, with Salvador Larroca, who had been working with him on Uncanny X-Men doing the art. Finally, Joss Whedon entered as the writer of the new title Astonishing X-Men, with John Cassaday as artist. X-Treme X-Men was cancelled. Also, the X-Men returned to more traditional (if not slightly revised) costumes, as opposed to the black leather uniforms from the movies.
In addition to this reshuffle of the main titles, many of the secondary X-Men books got new writers as well.