But I bet many novice developers have been exposed to Ruby and Python (and SVN) because they shipped with OS X. Let's let newcomers use git without a custom install, and maybe it will lead to more widespread adoption.
You don't need the latest version of git for init, clone, add, commit, push, and pull to work.
Macports is better than nothing, but not by much. I admit it's a real blessing when it comes to something complex with a lot of dependencies - if it works, but a lot of the time it's more trouble than it's worth.
I've personally seen it delete the data during a postgres update, and it regularly runs roughshod over config files, etc. It screws up installs all the time, which can be a nasty surprise since it doesn't clean up after itself properly (this happened to me when it put a non-functioning ssh in my path, leading to a bit of panic when I suddenly needed it urgently). It can't clean up obsolete, well, anything without the "force" option, spewing spurious warnings all over the place .. except when it turns out they weren't spurious and you find out it deleted something critical. It's slow as hell to list what you do have installed. The maintainers are sloppy and non-working packages sit in the repos for weeks at a time (hello, Erlang).
Like I said, it's better than nothing, but I don't think anyone should use macports for anything that could conceivably store any data you care about. You will probably need to nuke /opt and re-build everything from scratch periodically, so make good and sure there's nothing in there that you care about. However, if you use it with caution and bear in mind the necessity of a periodic rebuild, it can be a big help.
Personally, I've had more trouble with macports than necessary. (Mostly because whenever I type 'port', I still get command not found.) It's much easier just to download the source, ./configure, make, and sudo make install.
Thats because macports installs itself to /opt/* which isn't in your $PATH. Easy to fix. But macports still causes more problems then its worth. So does fink for that matter.
What problems? Package dependency problems? The worse that I've had happen is having to deal with broken packages. The amount of times I haven't had to deal with figuring out dependencies makes it more then worthwhile, IMHO.
You don't need the latest version of git for init, clone, add, commit, push, and pull to work.