Even those people with years of UNIX programming and systems administration experience may need assistance before they are able to pick up and install Linux. There are still aspects of the system that UNIX wizards will need to be familiar with before diving in. For one thing, Linux is not a commercial UNIX system. It does not attempt to uphold the same standards as other UNIX systems you have may have come across. To be more specific, while stability is an important factor in the development of Linux, it is not the only factor.
More important, perhaps, is functionality. In many cases, new code will make it into the standard kernel even though it is still buggy and not functionally complete. The assumption is that it is more important to release code which users can test and use than delay a release until it is ``complete''. As an example, WINE (the Microsoft Windows Emulator for Linux) had an ``official'' alpha release before it was completely tested. In this way, the Linux community at large had a chance to work with the code, test it, and help develop it, while those who found the alpha code ``good enough'' for their needs could use it. Commercial UNIX vendors rarely, if ever, release software in this manner.
If you have been a UNIX systems administrator for more than a decade, and have used every commercial UNIX system under the Sun (no pun intended), Linux may take some getting used to. The system is very modern and dynamic. A new kernel release is made approximately every few months. New software is constantly being released. One day your system may be completely up-to-date with the current trend, and the next day the same system is considered to be in the Stone Age.
With all of this dynamic activity, how can you be expected to keep up with the ever-changing Linux world? For the most part, it is best to upgrade incrementally; that is, upgrade only those parts of the system that need upgrading, and then only when you think an upgrade is necessary. For example, if you never use Emacs, there is little reason to continuously install every new release of Emacs on your system. Furthermore, even if you are an avid Emacs user, there is usually no reason to upgrade it unless you find that some feature is missing that is in the next release. There is little or no reason to always be on top of the newest version of software.
We hope that Linux will meet or exceed your expectations of a homebrew UNIX system. At the very core of Linux is the spirit of free software, of constant development and growth. The Linux community favors expansion over stability, and that is a difficult concept to swallow for many people, especially those so steeped in the world of commercial UNIX. You cannot expect Linux to be perfect; nothing ever is in the free software world. However, we believe that Linux really is as complete and useful as any other implementation of UNIX.