So, my first question and answer to the site, I believe, was: Recommendations for a usable, fast C++ matrix library?
It's gotten a lot of views and votes, but now that I'm a mod and I've been on the site for over 2 months, I look back at it, and I feel like it's gotten out of hand, and isn't a good question as posed because it's starting to attract answers that aren't so great. Since I wrote the question and answered it, I feel like it's my responsibility to fix it.
The question was not as focused as it could have been. I wrote the question because I wanted a library to use for a project I'm working on, and I spent a couple of days looking for an answer to that question. I knew that I'd be using dense linear algebra as I started out. I also knew that I might want to use sparse linear algebra later. I probably should have specified that I wanted to know about established libraries (i.e., ones with some sort of institutional backing).
My answer was also not as focused as it could have been. I listed 11 libraries in one answer, which is not good if one wants a list I tried to cover dense libraries, sparse libraries, and hybrid dense-sparse libraries, which reflects the origin of the question; I didn't know at the time if it would be good to stick with a dense library, or plug a sparse library into the project instead. (I still don't know.)
Given that we're starting to refine and sharpen the idea of what we want out of the site, how can I fix this mess? (I have my own ideas, but I'll post them after I've gotten some sleep...)