I haven't tested it, but I'm intrigued by Shuan Inman's Fever reader (http://feedafever.com/). Basically the idea is that you separate your feeds into two distinct types: essential feeds that you read completely, and supplemental, high-volume feeds (aggregator-type blogs, like Engadget). Then the essentials are cross-referenced with the supplementals to see what you're likely to be interested in.

I have a similar strategy, but instead of trying to manage the "supplementals" in my RSS reader, I try to a) identify them, and b) banish them back to the browser where they belong. Identifying them can be tricky, at least for me, because I tend to think that feeds I've been reading for a long time are essential, when often they're not. Removing a lot of politics blogs from my reader I swear has made me less stressed, and I don't feel any less informed.

I think the higher volume of content means we have to become better at selection — not only in choosing what we read, but also in identifying and not reading what is noisy and lacking in substance, even when tempting (ahem, HuffPo). Edit: and I'm not sure algorithms are the solution; I think it's something our generation will have to learn — to be our own conscious curators.