Much to its credit, Microsoft yanked the bad Visual Studio 2010 patch, KB 3001652, within hours of its release yesterday. Reports of the patch's hangs and errors rapidly piled in from all over the Internet.
Today we have another version of the patch appearing in Windows Update, and on Windows Server Update Services. Based on a very small sample, it looks like the new version installs just fine.
KB 3001652 has a convoluted history. Originally released last October, it was somehow re-released in this month's Black Tuesday drop, on Feb 10. The KB article doesn't mention anything about either Tuesday's or today's (Wednesday's) modifications to the patch -- the article hasn’t been updated since last October.
Microsoft's official Windows Update/WSUS patch list, KB 894199, doesn't list the Tuesday botched update, nor does it list today's apparently good update.
I have no idea why the patch was re-issued this month, what was wrong with the October version, why it had to be re-issued or updated, and why the botched patch triggered so many problems. Perhaps Microsoft will tell us.