Unwakeable 1.5.3 is available for download. This version is built off K2 1.0.3 and should work beautifully with WordPress 2.9+. You can head over to the Unwakeable page to get the download, or you can grab it here.
K2 1.0 added more support for WordPress 2.9. For example, K2 1.0 supports new WordPress features such as post thumbnail images. One of the more noticeable changes to K2 since the 1.0 release is the absence of SideBar Manager (SBM). It sounds like it was simply too much work to maintain SBM, and was beyond the scope of what K2 is:
It’s worth mentioning that the last remnants of the old SideBar Manager, or SBM, have now been removed from the codebase. It started out as a fully-fledged replacement for WP’s lacking widgets system and ended up as a patch-of-sorts to the widget system, allowing for widgets to be placed only on specified pages. But in the end, while the native widget system is still very much in need of an update, it didn’t feel right for K2 to try and cover that particular area of the administration interface. And besides, other plugins for doing just that exist already.
So instead of spending our time patching that system for an ever-changing WordPress, our time is probably better spent on more theme-specific functionality, like the rolling archives or livesearch systems, as well as keeping up with new WordPress features, like for instance Post Thumbnails.
Rather than break down all of what’s changed in recent versions of K2, I’m going to make it easy on myself and direct you to the K2 1.0 release announcement. Just know that Unwakeable 1.5.3 sports all the features found in K2 1.0.3. You can comment on this post or on the Unwakeable page with questions or comments.