Sequels and reboots

In The Mythical Man-Month, one of the most famous book about software engineering, Fred Brooks says, referring to software projects:

Chemical engineers learned long ago that a process that works in the laboratory cannot be implemented in a factory in one step. An intermediate step called the pilot plant is necessary [...] Hence, plan to throw one away; you will, anyhow.

I see this as a perfect reverse situation of movies production.
It is indeed true that in the motion picture industry sequels often ruin the feelings of the original movie and at least do not come close to its perfection (though they can surpass it in success due to advertising campaigns and public's expectations).
Consider these science-fiction movies as an example:

• Star Wars: it is widely believed that no sequel or prequel can measure up with the original A New Hope. The final, which I don't want to spoil here, is probably the most scene in the history of the genre.
  
• The Terminator: although every sequel contains the catch-phrase Come with me if you want to live, the original 1984 movie is still the most revolutionary.
  
• The Matrix: should I say anything?
  

In software projects instead the 1.x version is usually the first version to throw away before upgrading to one of the subsequent world-changing releases:

• The Linux kernel: today at version 2.6 it finally supports the majority of devices and will never require you to insert a driver cd (in the worst case to compile drivers, which is really annoying).
  
• OpenOffice.org, whose 3.x version is becoming more and more diffused and has recently reached 100 million downloads.

Open source projects often are reluctant to mark the 1.x release of a software before it is really complete and tested. Although this humbleness, often they experience success in the releases that come later, maybe for the fact that is the wide adoption of the first stable version which exposes for the first time architectural problems and other issues in a large installed base. The developers effort is alzo minimized since a 2.x version sees the light only if there is enough momentum and following from the first release.

So why not citing php sequels, which has reached version 5.3?
Extending the cinematographic comparison, often we watch reboots instead of sequels. This kind of movies is very fashionable nowadays:

• 007 reboot, which starts with James Bond earning his 00 license.
  
• Batman  Begins and The Dark Knight, that rewrites the franchise from the moment Bruce Wayne became Batman.
  

Rewrites is the right word, since a movie franchise reboot corresponds to a major code rewrite. A rewrite is different from an upgrade since not only it breaks binary and Api compatibility, but it consists also in throwing away entangled and coupled code to write from scratch a new solution. The border between the two is not strictly marked, and many major releases are in fact rewrites which maintain the same name for brand popularity reasons.
Such rewrite is different from a movie reboot in the way that it maintains some continuity between the old and the new version, for example in the Ubiquitous language, but it is much more dangerous and it can lead to a never-ending development phase (anyone knows Mozilla suite's fate.)
Ports can also be considered reboots if started from empty source files, and often the original source code is unavailable. Today the most famous ports start from a commercial application to reimplement as an open source one. Forks and ports of open-source application instead recycle code and remain connected with the original project.
Besides the issues in rewriting from scratch, there are successful attempts of reboots in the open source software ecosystem:

• Apache 2 is a substantial rewrite according to Wikipedia; Apache original duct-taped version gained its name from the phrase a patchy web server.
  
• Php rewrite before version 3 and 4, which saw the introduction of the Zend Engine.
• Grub, the bootloader for GNU/Linux machines, has recently been upgraded to the complete rewrited Grub 2 in Ubuntu, but no one I have seen using Karmic Koala noticed the difference.
  

Are you writing a reboot, a sequel or an original movie? :)