Using Mercurial, is there an easy way to diff my working copy with the tip file in the default remote repository

hg clone http://hg.kublai.com/mercurial/extensions/rdiff

[extensions]
rdiff=~/path/to/rdiff/repo/rdiff.py

hgrdiff() {
    hg commit -m "temp commit for remote diff" &&
    hg diff --reverse http://my_hardcoded_repo $* &&
    hg rollback      # revert the temporary commit
}

hgrdiff <filename to diff against remote repo tip>

hg incoming --template {files}