2 packages available for Ubuntu Server 12.04 that I've come across are horribly out of date: Nginx and phpMyAdmin. I use PPAs to manage these, but I've often wondered why these packages are so out of date while others are not (PHP5, MySQL, for example).
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The Ubuntu MOTU ("Masters of the Universe") team does.
They have to balance stability and using backported patches against using a new version and risking introducing bugs (in your case to a stable LTS version). They also have to prioritize what is important and to spend time on trying to update without breaking that package.
It could just be a case of not being familiar enough with a piece of software to know the kirks that could break it, so they may leave it to the "pro's" for that piece of software to make a PPA.
And, of course, I'm sure they would always love to have more help, but it may not always be feasible for everyone (depending on what they know) to jump in and fix the things that are bothering them.