According to the blog post the connection stuff to the official server will abstracted off and stay closed source.And great news about Osu going open source. I guess that means it will also have access to it's leaderboard?
The "new style" sliders are the one that used GL Shader. Thoses will not draw now, but I'm supposed to have desabled the use of the new style sliders, so I was excpecting them to still show? I have to re-check the code.