Because I encourage the entities to get hands on with newer versions and most entities with whom I work have multiple instances of Moodle on same server, yes, I do have a 'instmdl2' script - which gits the moodle code, creates the data directory for the instance and creates the database as well. Takes only one parameter ... the name of the moodle instance (the [directory] as mentioned before).
However, once one is installed via git, to update one all one needs to do is to change into the moodle instance directory and type: 'git pull'. That's it. Not really worth scripting a simple line like that ... just have to rememeber it. That being said, however, one could build into that 'git pull' script tar balling the code directory, the data directory, and doing a mysqldump of the DB ... thus backing up everything before updating via git.
Git works like rsync with certain switches ... git gets only the files that have been updated. So to get the code fix for the issue with Moodle 2.4 for window links + any other issue that has been fixed, it took all of 3-4 minutes at the most (and most of that is stepping through the web interface notifications). The only other thing is to re-set ownerships of all files since git was issued as root user.
Wget won't go away ... that's just downloading the .tar.gz or .zip file. It's handy to know more than one way ... period. If there are issues with git for some reason, then the 'fall back' to 'get 'er done' is the 'long way'.
Still use wget on my own server to acquire the latest package (.tar.gz) when the entity firewall am working behind hickups and won't allow Linux servers to acquire the files.
'spirit of sharing', Ken