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WordPress and WordPress MU Merged?

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At the last WordCamp in San Fransisco, apparently Matt Mullenweg announced that the codebase of WordPress and WordPress MU (multi-user) would be “merging.”

What exactly this means, and when exactly it’s going to happen, I’m not sure. WordPress 3.0 is the version number floating around when it’s supposed to be introduced. Again, this is uncertain at the moment.

Andrew over at WP Fun also pointed out that Habari already has this feature built in. I believe Movable Type also has a similar multiple blog features as well.

Personally, I like normal WordPress even though I have multiple WordPress blogs. It just makes sense to keep them separate just in case I ever need to move any. I realize this may not be the most efficient way to run multiple WP blogs, but it’s not that big of a deal to me to keep them maintained.

Although this isn’t likely to take place for a couple more versions, how do you feel about this merger? If anyone has any more information on this, I’d love to hear about it in the comments.

Update (June 2, 2009): Okay, maybe myself and a bunch of other people are confused on this whole “merger” thing. Lorelle just posted this on the Blog Herald about what Matt may have really meant when he mentioned the “merger.” Maybe it’s not the self-hosted WordPress software that is getting changed, but the actual website that will be integrated into WordPress MU. Again, I think it’s probably best to wait for an “official” clarification from Matt, but thought this would be worth updating the post with.


Leland Fiegel was the original founder of ThemeLab. He is a web developer who loves WordPress and blogging.

  • Andrew

    I don’t really know anything about MU, except that I have read a lot of comments from people over the years saying that theming and plugins require some differences.

    That aside I have to wonder how big a code change this really is. I mean, is MU just .org with an extra wrapper around it or are there fundamental architectural differences?

    Hopefully someone who has more knowledge of MU will write something soon.

    • Andrea_R

      Themes, not so much. Single WP themes “work” on WPMU, you just can’t edit them.

      The plugins that don’t normally work are ones that can’t find the different blogs; this will require some plugin authors to bone up on their skills. ;)

  • Leland

    @Andrew: Same here. I read somewhere else that this merger would cause a lot of “code bloat” although looking at the file size differences between the two, it doesn’t look very significant at all. This leads me to believe it may just be an “extra wrapper.”

    I’m also hoping for someone more knowledgeable on MU to weigh in, because like you I don’t know much about it at all.

  • Andrew

    It looks like there is some discussion in the WPTavern forum about such things.

  • Su

    Andrew over at WP Fun also pointed out that Habari already has this feature built in. I believe Movable Type also has a similar multiple blog features as well.

    There are some subtleties being glossed over. Any of these systems being able to manage multiple sites is just a bullet point that ignores the question of what you can actually do with that ability.

    Movable Type can manage multiple sites/blogs, and they’re stored in the same database. There are core features allowing the template language to pull entries from blogs other than the one in context, or even across multiple blogs, for producing collated lists, etc.

    Habari’s implementation is defined in their wiki. Probably the most important bit is that beyond sharing the app files, the sites being managed are completely separate entities, down to each having its own database. This means that not only do they not share data cross-site/blog, they actually can’t. (Given the project’s development status, all of this has a heavy “at the moment” disclaimer, of course.) Habari seems to have a pretty aggressive policy of keeping the core simple, so I’d guess MT-style cross-blog templating would more likely be implemented as a plugin and maybe even stay that way.

    Someone else will have to fill in regarding WP/MU’s capabilities, or what the plans are. I’ve spent no real time with it. I think I recall it does at least use a single database, though, so even if the template language proper doesn’t have cross-blog abilities, it’d be a bit easier than with Habari to just use raw PHP to get at the data.

  • Leland

    @Su: That’s a very good point about what you can actually do with a “multiple blog management” feature. Judging from your website URL, I’m assuming you’re primarily a Movable Type user? It’s always nice to have another perspective, and I appreciate the thoughtful comment.

    • Su

      Primarily MT, yes. And I’ve been doing some research into Habari lately. Funny enough, I’d been asking around about the multi-site feature just the night before.

  • Andrea_R

    Just weighing in with I don’t know much more than you do. I can see a couple ways they may go, but I won’t even know for sure until I see it in trac.

  • Leland

    @Andrea: No problem, seems this was just really preliminary news anyway. I guess we’ll just have to wait to see how it goes.

  • Pingback: Wordpress MU & Wordpress to Merge :

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  • Leland

    To those of you subscribed to the comments, you might want to check out the update I just appended to this post, as well as this post by Lorelle at the Blog Herald.

  • Pingback: WordPress and WordPressMU Merged: Whoa! | Bloging Bloging()

  • Dane”IT Training”Channel

    Many bloggers have a lot of concerns about MU. I hope someone will post an update about it.

  • Leland

    @Dane: What “concerns” are you talking about? Care to share any links to discussions regarding this?

  • Tadd Mencer

    Honestly I think this is pretty slick. I use MU for a large site I’m building for personal projects. A company I’m working for is using WordPress as their base CMS and I’d love to see an MU drives ‘core’ site rather than all these mini-blogs.

    IN the end I suppose it really comes to whether or not we need the feature bloat. If Joe Smiles is only doing one or two blogs he doesn’t need all the extras – they only get in the way and distract. If he wants to do a multi-blog site he can go get WPMU.