China has unblocked access to the code sharing site GitHub, after at least partially blocking it last Thursday. The reasoning behind blocking GitHub isn't known, and it's not clear why they would block it as it has no affiliation with any government or political views.
The unblocking is likely due, at least in part, to Google's former head of China operations' post: "GitHub is the preferred tool for programmers to learn and connect with the rest of the world. Blocking GitHub is unjustifiable, and will only derail the nation's programmers from the world, while bringing about a loss in competitiveness and insight."
The post was made on Sina Weibo, China's equivalent to Twitter. The message was re-posted over 80,000, which helped spread the message that GitHub should not be blocked. Users may still have trouble accessing GitHub, as some of the DNS servers still have the old cached routing information from when it was blocked. The should clear up soon.