I have to admit that i jumped over to using Habari for my blog mainly based on how well designed and obejct oriented the underlying API seemed from the documentation. Coming from looking at Drupal code all day, which is painfully NOT Object Oriented, yes with capitals, the code is more readable and, so far, less mysterious.
Don’t believe me? Go read the instructions for Creating a Content Type. Like Drupal, it depends on function name conventions for some hooks, but beyond that everything else is nicely encapsulated in a proper class.
But I haven’t developed my own plugins yet, although I have an idea for one. My main impressions are from installing it and using it.
The installation itself is very straightforward, at least on par with WordPress. If, like me, you find yourself installing it multiple times, one can Predefine configuration settings and not have to manually enter them each time.
The admin interface is elegant and useful, certainly less cluttered than Drupal’s admin pages. A simple pull down menu in the top left corner of the page lets you add posts, configure plugins, and access other admin functions.
The plugin system is in a state of flux, due to a change in how plugins are defined/discovered by the system between versions 0.6 and 0.7. This means a lot of plugins are available for the former, but maybe not the latter. It’s also difficult to track down a solid list of plugins, so I’ve been using http://svn.habariproject.org/habari/trunk/htdocs/user/plugins with svn:externals to install and update plugins.