This isn't an actual script ... more like a recipe even though it could be converted into a script

wordpress_repo_release_recipe.txt

# git commands executed within git working dir
git commit -am "Bump to 1.5.0"

git push origin master

git tag 1.5.0

git push origin tag 1.5.0

cd /path/to/svn/working/dir

curl "https://github.com/cool/project/zip/file" > project-1.5.0.zip

unzip ./project-1.5.0.zip

rsync -av --exclude=".svn" --delete project-1.5.0/ trunk/

# any new files NEED to be removed here ... if there are any!!
svn rm ...

# any new files NEED to be added here ... if there are any!!
svn add ...

# Just here to make sure that the files are properly sync'ed
rsync -nav --exclude=".svn" --delete project-1.5.0/ trunk/

svn copy trunk/ tags/1.5.0

svn ci -m "1.5.0 Release of My Cool Project"