I don't get why there are some many overflow.com sites. It was already hard to figure out which overflow.com to post to, and now it's even harder. The only "solution" is to post to them all. Or aggregate them as overflowoverflow.com as someone else suggests so you only need to read & comment on one.
whichoverflowshouldIposttooverflow.com
someone should make overflowoverflow.com for all these sites