Absolutely. I coded up a replacement using the GitHub API:

http://gilesbowkett.blogspot.com/2010/10/node-miniapp-minima...

It broke when they changed the API, but by then I had found http://defunkt.io/dotjs, which allows you to execute any code in a ~/.js file for a given domain.

So I put $("div.news").hide(); in my github.com.js and instantly had a more relaxing, comfortable life.

I completely disagree with this part of your post:

Facebook has done a really good job solving the problems of information overload and would provide a good model.

But I do agree with these:

The most important step is to group updates from each project. Right now half of my news feed is comments on a single repository. Those should take up only one or two slots. The next step is to filter according to some metric of "interestingness."

My advice is do it and share the hack. I think the best way to find trouble spots in your UI is to find out what people are writing hacks to work around.