Wow, that's a pretty blanket statement! Open source is only one of many reasons why WordPress has been growing more rapidly than Movable Type. But even at the open source level there will be a significant difference between the two: WordPress has a single license model and Movable Type will have a dual license model. This means that all of the WordPress code is available under a single GPL open source license. Whereas it looks like Movable Type will release some of their code as an open source version and keep the rest proprietary and available only via a traditional paid license.

Considering that some of the great open source projects of our time, from MySQL to Firefox to Ubuntu rely on a combination of open and non-OSI licenses for their work, I don't think you should be shy about the fact that it's part of your business model as well.

That's also based on my understanding that "all the WordPress code" is *not* available under a single GPL open source license -- or is it possible to download everything that runs wordpress.com and run a clone site like lots of people do with our LiveJournal code?

"how is our selling of a commercial Enterprise product different than Automattic having KnowNow sell a commercial Enterprise product that's not GPLed?"

KnowNow sells enterprise support and hosting based on stock WordPress MU. They do not sell or license WPMU itself, since that's 100% open source. You guys charge for the enterprise version of your software. We give away all the software, including so-called enterprise features, and charge for value added services like support and hosting.

"or is it possible to download everything that runs wordpress.com and run a clone site like lots of people do with our LiveJournal code?"

Yes, that's possible and there are hundreds of sites that do it. Check out edublogs.org for example, they are a "wordpress.com for teachers".

Another example that touches on both of your points is our release of HyperDB (http://comox.textdrive.com/pipermail/wp-hackers/2007-May/012893.html), the database class we've developed for wordpress.com. It represents lots of development hours to figure out things like replication, failover and redundancy among multiple datacenters running WordPress. Most companies I know would license something like this as a "enterprise class database upgrade pack" for lots of money. We give it away open source.

MySQL does do a dual-license of their code, which I personally disagree
with as I believe it misaligns the incentives of the company and
community over time. If you look at the kerfluffle around the community
edition of MySQL you'll see an early manifestation of this.

I'm not familiar with non-open source parts of Firefox, perhaps you
could expand or link?

Ubuntu is an operating system so not directly applicable, but 99.99% of
its core functionality like the kernel, filesystem, office apps, desktop
manager and more is completely open source, in line with their
philosophy. The main exception they begrudgingly make is for certain
binary device drivers, and those are kept in a different repository from
the main code and you have to go out of your way to use them, much like
Debian. Ubuntu is now even investing in Gobuntu, a distribution that
meets the ultra-strict requirements of FSF and Richard Stallman. (Of all
the currently available distributions, only 3 make the cut, and you've
never heard of them.) Perhaps you were thinking of Red Hat or SUSE instead?

For good WordPress.com clones, check out edublogs.org or unblog.fr.

The answer is yes, with the caveat that WPMU releases only happen every few months whereas we add new features to wordpress.com every week. So there tends to be a lag between new features showing up on wordpress.com and the time when those features can be packaged as part of an official WPMU release.

My problem with MT 4.0 is the way it disables or breaks older plugins. I was very selective in using plugins, and only used them from some of the best coders. Plugins such as dirifyplus, regex (which is the first thing that made MT usable and should have been folded into the main code to begin with!), and a few others.

Now, not only are they broken as plugins, they cause the entire MT thingy to spew a 500. Not kosher. If a plugin is not supported, a sophisticated piece of software should just ignore it and report it to me as a message.

This is the problem with using old drivel like Perl. Great for server side admin tasks, horrid for functionality such as this. Some of the new languages, just work and are easy to edit.

IMNSHO, MT 4.0 is hardly a sophisticated "major update". Putting menus from a cumbersome clickety-click interface into something just a little bit simpler with new colors/gradations and a slow Flash bit on the front page, does not make a big release. I'd liked to have seen MT pull up its socks and grow up as a piece of software that can be extended easily. I just do not see the sense of using Perl as the main backend. This is the reason I'll switch to something like Wordpress -- it may not be truly static but it is very, very easy to edit and the community is much faster in responding (go to MT support forums, read up on all the rigmaroles people're going through thanks to this golden upgrade, and see how their posts are collecting cobwebs).

With regards to the extensibility of the platform, being a plugin developer I know that MT4 is literally light years ahead of it's predecessors (and I would hazard a guess ahead of competition too). The amount of new frameworks (from ratings to extensible archives, the new registry, the widgets framework within the app, the fact that the app pages share the same templating language as blog templates) has been mind boggling.

Stop by the support forums of Movable Type when you have a moment to see enough documented proof of MT4's PITA bugs. It's not just me. The support community seems to be in cobwebs these days. Many posts go for days on end without any input from anyone. Instead of posting defensive stuff on blogs such as these, the MT staff should probably be allocating their time helping out their users, who will do the marketing themselves.

Not only are the plugins not working, the entire MT 3.35 installation has been rendered useless because my old archives do not work. I changed the *.html extension to *.htm in my Publishing Settings, and the MT4 thing is still spewing out *.html files. And these *.html files are broken, because the plugins I have been using are not working anymore.

I tried a completely fresh install of MT4. It is slow. The menu system is not amazingly well designed in terms of getting quickly to the most commonly used things. (I downloaded the "Bookmarks" plugin, but that should have been a 101 feature of any meaningful upgrade). It does not matter to users whether the innards of the plugin architecture are much better. The darn thing should work first. Too much longer of a wait for my posts on the support forums, and I'll be among the hordes that are going to Wordpress because that community works. You search for something on their site and you usually find a lot of meaningful stuff. Try searching "paginated archives" (supposedly a new MT4 feature) on the movabletype website and bob's your uncle.

Cheers.

This may make people like plugin developers reel with pleasure, but this is not an "improvement", this is how the architecture should have been from the beginning, so this is merely a "correction". None of this would have been an issue had the platform been in PHP, for instance, instead of Perl.