I personally think I'll follow a lot of people on here who I find interesting but that wouldn't reflect whether I want to follow them on Github, which will be if I want to see their code. There's a much closer gap on here than other social networks to them being the same, but…
Yeah, I wouldn't be against that :)
I can see why some people might like it I suppose. I personally keep my follows on Github fairly slim and wouldn't want my GitHub feed to be too noisy and not easily digestible.