When it come to categories, the developers behind WordPress are so confused it’s not even funny how many times they have changed how they handle categories. From different categories for posts and links to merged categories, and now tags and separate categories for posts and links. There is equal confusion when it comes to links, from calling it blogroll to links to bookmarks.

Why be wary of WordPress 2.3?

Link category hierarchy support in versions < 2.3 was more accidental than intentional. That's why it doesn't work so well. 2.3 removes the half-assed support for it.
-Ryan

Well, this only applies to those who do more with WordPress than just a default blog; the more advanced users of WordPress. I have been testing WordPress 2.3 since beta 1, and one of the main issues is what they have done with categories, especially with blogroll. Currently you can have hierarchies of categories which can be used for grouping blogroll, but with 2.3 there will be only one level of categories, and so if you had elaborate category hierarchies setup, you will lose them when you upgrade to 2.3.

For majority of users of WordPress, this should not be an issue, as they use blogroll as just a blogroll, and don’t do more complex hierarchical category groupings of their blogroll. In the case of Counterjumper, posts and blogroll use the same categories. So when you click on the post category, you see just the links related to that particular post category. If there are other users of WordPress with similar usage of categories, then your sites will not function correctly when you upgrade to WordPress 2.3.

Tags
In 2.3 a new feature is the ability to add tags to posts. It’s a good addition, but there seems to be a conflict with categories, creating more confusion. Then there is the lack of foresight, they provide tags feature for posts, but no tags feature for blogroll.

Why does WordPress look at Blogroll as just links to Blogs?
Finally, why think of blogroll as just a single list of links to other blogs? Internally it’s handled by link-manager, the functions are called bookmarks, why not think like deli.icio.us when picking features for blogroll? A lot of WordPress users use it more than just a blogroll, and I feel it can be more powerful as a bookmarking feature than just a blogroll.

Finally to conclude, even though I say be wary of WordPress 2.3, most regular users of WordPress will not have any issues with it, but advanced users like me might not be able to upgrade to it!