[Osiris]

Source Should you upgrade your Linux distribution?

So you’re working with Ubuntu 8.04 or Fedora 10 and you’re jonesing over the new release of your distribution. You have always kept up with the most recent releases, but time is critical and your machine is working well. How do you know if you should upgrade? Is it worth it? What would stop you from making the upgrade?
In this article I will give you reasons why you should and should not make the jump to the most recent release of your distribution. Hopefully, after reading this you will either want to immediately download the latest ISO or you’ll close your browser and go about your merry business.

[Jayce]

If it aint broke - don't fix it. I upgraded my Ubuntu image server at work, but only because I could get the image server working from ground up in less than 45 minutes if I had to drop back to 8.04. Plus an image server isn't exactly a file server, where it's a bit more important to stay running.

[kmote]

I agree with jayce, it's a bit like BIOS updates - only do them if there is something specific you want/need.