Im in scotland and have the same problem, so its not just china! I just got my mac a couple of days ago and all seemed to be fine. Then i bought music from itunes and started downloading it. Everything went mental! It was taking 15mins to download one song, now it wont let me into the itunes store at all, says im not connected. I flipping am!!! So im very frustrated but am glad it seems to be happening to many people not just me! Does anyone know if apple are actually doing anything? I still have half an album to download!
I work for a dynamic little company that may have a workaround for the iTunes block. However, we need a few people in CH who can do a quick test of it for us. Nothing too scary, as you don't actually have to download anything deemed 'bad' by the authorities, etc. we just want to see if you can get to iTunes and get at Madonna (ick) or whatever you were listening to before. After that we'll let everyone decide what to download in a secure, private fashion.
If you're in CH and interested in giving us a hand, please email me at email@example.com with some (vague) location info, and we'll gt back to you ASAP.