The topics on Slashdot are about the same quality as they were last 5-7 years--not great, but still nice and "relevant to my interests." The wording of the article summaries is still pro-Linux anti-Microsoft (and now) anti-Apple inflammatory, and still hilariously poorly edited or vetted. However, that was always a charm of the site, in a way.
The difference is that some 5 years ago, in the face of an anti-Microsoft post, for example, people would chime and say "You know, actually I have developed a great project with ASP.NET and here's why it's good and worked well for me." Or people would post detailed responses, like we see on Hackernews.
Now, I've come to a point where I see so little of those good comments and so much of the inflammatory or ignorant or terribly-humored comments, that it's just not worth my time anymore. I can get the headlines from anywhere else and in the tech world, it's the discussion behind the headlines that's the valuable thing.