It has yet to be made public exactly what version of Linux will be preinstalled, what that will look like, and how that will fit in the scope of using the PS3. It seems likely that the PS3 will load similar to the PS2, giving the user a simple hardware browser - and that the hard drive OS would be loaded from there. Regardless of how they implement it though, the very fact that a flavour of Linux is going to be preinstalled means that it should be relatively easy to replace it with another version of Linux and potentially even other OSes that can be eventually ported to the PS3 hardware.
If you've ever used an alternative operating system, whether free or proprietary, you've probably had issues getting your hardware to work properly. Even the most valiant attempts at supporting hardware is bound to miss some sort of configuration that the development team didn't expect, and this leads to often complicated workarounds due to lack of manufacturer co-operation or even outright hostility. As a result you can never be certain that Linux or BeOS or FreeBSD will be as smooth as something like OSX is, because with OSX, Apple controls the hardware and so their software knows exactly what drivers to ship on the CD to support the hardware they sell. Simple.
With the Sony PS3 hardware, this will provide alternative OS vendors a similar opportunity to what OSX offers to Apple hardware right now. It will be a stable platform with known hardware, and if they can ship a working Linux implementation this means that the specs will be open enough that any operating system that desires to can probably also be ported to run on this machine with little fuss. The PS3 will be a good platform for many years, so it won't be the moving target that supporting PC hardware often is - only one driver needs to be implemented once instead of having to keep up with the crazy treadmill and a thousand vendor choices.
Right now with my current operating system, Ubuntu Dapper, many of the components are built generically so they will work with a variety of hardware that I will never use. Each time it boots my OS does a check to see what hardware is installed and configures itself accordingly. This is a actually good thing for a computer operating system, and it allows me to do neat things like swap the hard drive out and put it in a new machine which still boots perfectly fine on the new hardware (providing that it's supported by Linux of course). Packages are compiled for supporting even the ancient Intel 386 processor, while I use a much more modern Pentium 4 chip. This all changes if an operating system decides to target the PS3. They can compile packages directly for the Cell processor, support only the video card that ships with the PS3 and support it well. Things that can be hard with alternative OSes like Bluetooth and WiFi can be simplified because there is only one choice for each one - even if a driver must be hacked up there is the advantage of everyone having the same hardware it will reduce the duplication of effort that multiple drivers would force. The PS3 is a standard platform which will greatly reduce the complexity of hardware support - so OS developers can focus on making the software perform on the known hardware as best as possible instead of having to deal with crazy contingencies.
It must be said that the PS2 also supported Linux even with a Sony supplied CD, and it was hardly the revolutionary reaction that I predict could happen with the PS3. The difference is that the PS3 comes with a hard drive preinstalled. This means that unlike the standard PS2, with the PS3 you won't have to constantly swap CDs around or run the OS off the CD as if it were a LiveCD. The PlayStation is a gaming device, and why would you want to run a non-gaming OS if you had to keep swapping out the CD to do anything fun with it? But if you can run it off the hard drive, this means that you can seamlessly use the device for both gaming and general purpose computing uses. Additionally, high-definition video support will help display text better especially in combination with the digital displays that are becoming more common for in high-end media centres.
I encourage developers to plan ahead in order to take advantage of this opportunity - funded Linux distributions like Fedora, Ubuntu, SUSE, Mandriva, etc. should do their best to get development kits for these machines (if they haven't already) in order to be prepared for the launch later this year. If executed properly, and there seems no reason why it can't be done properly, the PS3 could be the first time that even the most non-technical people can safely install and use an alternative operating system such as Linux without encountering any problems. The holy grail.
About the author:
Ryan Thiessen is a programmer and free software enthusiast living in Seattle, WA but insists that despite this he is still as Canadian as hockey and poutine...