K2 - Sub-Categories for joomla are here!
K2 is now updated to version 2.0.0 and there is a new dedicated community site. To quote lead K2 developer Fotis Evangelou "Why wait for Joomla 1.6? K2 provides ACL, nested categories etc now"
Artisteer - The Death of the Joomla Template Club
Artisteer has been considerably updated with more features and now supports more CMS platforms and is available for Mac OS X users (beta only)
JCal Pro - The Joomla Calendar
Version 2.1 is now available with multiple calendars, public/private events and more advanced repeat event handling.
Joomla Developer Showdown
The showdown will start on July 2nd. Full details of the component specifications will be released then.
Built for Joomla
Sadly there has been no interest in this. I still hold out hope though.