There's actually been a lot of traffic in the change log for stable, with a lot of updates going on, but by default this means only relative only minor updates, bug fixes and security flaw fixes. So there won't be any major upgrades or version bumps. Slackware 14.2 now has the 4.4.132 kernel available in the repository as of May, staying with the long-term 4.4 kernel line. This "kernel upgrade is being provided primarily to fix a regression in the getsockopt() function, but it also contains fixes for two denial-of-service security issues", so this is a really recommended upgrade if you're not already running your own kernel or a higher version.
On the desktop front Eric Hameleers is continually providing updates to several packages he has opted to offer and maintain, most of all the Chromium browser with Pepperflash-plugin and monthly Flash-Player security updates. Also the Widevine plugin, the popular VLC video player with codecs already compiled in to the package for ready and immediate use and his Ktown repository with newer versions of KDE than was originally shipped for both stable and current. It may also be a bit of a testing ground for KDE Plasma for the next Slackware release but that is just my interpretation. Eric also offers updated and compiled versions of LibreOffice and other packages if you care to browse his repo.
Besides the above and the venerable SlackBuilds.org there's also MATE for Slackware for those preferring that desktop, as well as CinnamonSlackBuilds, both maintained by Willy Sudiarto Raharjo who has been active in the community for a long time and also runs a blog at slackblogs. Check out the GitHub accounts pages for those projects.
As you can see 14.2 is still very much up to it. Slack on!
UPDATE: LXDE and LXQT packages here.
The Salix distribution has a wealth of applications in their repositories and as they are basically a stripped-down, slightly customized version of Slackware in terms of artwork and a few additional admin tools it remains fully compatible with upstream, so it should be possible to install and use them without asking for trouble. However, as always, you need to make sure dependencies are fulfilled. The Salix team are also offering a now outdated MATE 1.16 in their repositories which one probably wouldn't want to install at this late stage.
List of Salix repositories.
Salix package search.
