Not only is
Ubuntu 11.04 out there, but Slackware 13.37 has now been released as well.
Slackware 13.37 has been in development for about a year and it includes Xfce 4.6.2, KDE SC 4.5.5, the Linux 2.6.37.6 kernel, GCC 4.5.2, updates to X.Org including the use of the Nouveau driver, and updates to the Slackware package management tools.
More details on Slackware 13.37 can be found on
the Slackware project web-site.