First of all, let me just say that this post is how I think canonical plugins should be and be treated. I have taken absolutely no regard to what the WordPress development team have said up until now whatsoever, so no matter if I agree or disagree with them, or if something has already been said and decided, it might be in the post below.
Canonical plugins are supposed to be some sort of official semi-core like plugins, backed by the development team. As such they will fill important (or rather, asked for) features that won’t make it to the actual WordPress core. I like this, I don’t think WordPress should be filled to the brink with features not all users should need. Keep the core simple yet versatile, and use plugins to expand it. It also makes sense that the core development team works on some of the more important plugins, to make sure that there are semi-official options for users unsure of what to extend their sites with. It adds a sense of security to the platform, which I think is a good thing.
I do not, however, think that canonical plugins should be used for developing a Twitter widget, for example. That is too trivial. A backup solution (much like the excellent WP-DB-Backup plugin), security scanner, caching with something like WP Super Cache, proper e-mail blogging support, a subscribe to comments solution, and things like that makes a lot more sense. The same goes for mammoth projects like BuddyPress and bbPress, both supposedly due to be canonical plugins in the future.
WordPress is often seen as a somewhat bloated blog platform. That interpretation is wrong if you ask me, this is a CMS and as such it is a lot bigger than a traditional blog platform, if there is something like that these days. Blogging is, after all, just another word for web publishing.
Anyway, the addition of canonical plugins is a great first step to focus the core, trim it down and offer a more modular online publishing platform. I would like the WordPress core to be as tight as possible, and then we can extend it with plugins. More or less like today, but trimmed down to the essentials, moving the rest to canonical plugins. Posting by email is a good example that has been mentioned previously, it is an addition to the core features and hence should be a canonical plugin.
There are some concern about canonical plugins clashing with the current plugin community and ecosystem. Official plugins for Feature X will make any other plugin doing Feature X obsolete. I disagree, if there is a better plugin than the canonical one, it’ll be successful. What the community should perhaps worry about is how the canonical plugins are presented compared to regular plugins, but then again there isn’t much criticism against the push for plugins like Akismet, PollDaddy, IntenseDebate and so on. Why did this suddenly become a problem, and why isn’t it one today?
I’ll tell you why. These are great plugins. As long as the canonical plugins are great, no one will complain. And why should they? The problem will only arise if there are better alternatives available, but only the canonical plugins are getting the push on wordpress.org. Then again, why create a canonical plugin if there are viable options already?
Trim the core, move non-essential features to canonical plugins, and push anything excellent from the community. That’s the way to lift WordPress to new heights, says I.