Blizzard knows about it - it is apparently an issue with their trackers, like the error messages say. There are, however, some patch mirrors they recommend, at least for Windows users, if you want to get patched up in a hurry. Of course, patching now isn't much use, since the servers won't be up for a little while, but it does give you something to do. I haven't seen any Mac mirrors floating around yet, although I'd bet that the trackers will be fixed before the servers are up.
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