The same applies to any news source though, doesn't it? Newspapers, TV, HN/name your favourite news site - all will have articles you don't want to read, mixed with those you do. To me, it doesn't seem like that much of a chore to skim through and pick out what's interesting to me, and an RSS aggregator acts as a prefilter, further reducing your search space.

I guess what you're looking for is something with some level of intelligence as to what you're likely to be interested in reading. Maybe that's the next step in the evolution of RSS aggregators - software that takes an RSS feed and filters it based on learned preferences? On the other hand, sticking purely to 'what you like' could lead to a sort of tunnel-vision where you miss the odd random article that captures your imagination but lies outside your normal tastes. That is, of course, a problem with aggregators in general, and is one reason why I keep reading HN and don't just stick to my RSS feeds.