I like Slackware. It's the oldest Linux distro there is, it's slow in its development cycle (which means it's very stable; only what works gets incorporated), and it's the one distro that's truly Linux. What you learn with Slackware can be carried over to all other distros. It's the most Unix-like Linux out there. There's an old saying about it:
Learn Redhat, you know Redhat. Learn Debian, you know Debian. Learn Slackware, you know Linux.
Okay, the problem with Fedora is that it's a development test-bed for RHEL, which gives it a very short development cycle (9 months, if I remember correctly). I was introduced to Linux with Fedora Core 2, in 2004 (Slackware was up to version 10). They're now up to Fedora 9 (Slackware is now at 12). 7 full version increments in 4 years. There's also a lot of packages still in development when the latest core gets released, meaning there's a bunch of brand new, untested software being shipped. Why? So the community can test things, fix things, and in the end the next release of RHEL can incorporate the new packages Fedora users fixed.
Don't get me wrong; I like Fedora (it's Linux, after all). It just moves too fast to stay current, and I'm not a developer.
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