Interesting decision. In practice I don't think this will change a lot, because it's been years since Slashdot was primarily the personal project of Malda; from what I can tell, he's been "just another editor" and a bit withdrawn from the decision-making for a few years now. But I can see wanting to do something else.

For all its downsides, Slashdot is a quite interesting experiment imo.

In terms of form: It was one of the first (the first?) widely read tech blogs, in the sense of something that posted about technology in reverse chronological order, with a comments section below it (the comments section was even threaded). The idea of having users submit stories and write blurbs was also fairly novel, and has led to several different directions. Kuro5hin and MetaFilter took it in one direction, expanding from blurbs to more general kinds of article submissions (and Kuro5hin switched to voting rather than editorial curation), while Reddit/Digg/HN took it in the opposite direction, paring it down to link submissions with no blurb (again with voting).

In terms of content, imo it was a main way, especially in the late 90s, that a generation of tech people were introduced to things like the EFF, free software, problems of software patents, driver support for Linux, hardware hackability, and other such techno-liberty type things. Those predated Slashdot, of course, but it sort of crystallized a community on the web, alongside those that had previously been organized mainly around mailing lists, Usenet, etc. It also gained considerable mindshare for those ideas from a broader set of readers who weren't necessarily "activists".