Cheers MysticG, was going to do that myself this morning
I've noticed another issue on this very system this morning due to SP3.
I have physical drives A through to F (hdd's and twin DVDs), G, L and N as mapped network drives.
Plugged in a USB storage drive this morning for first time since the update. Found it, connected, got the confirmation in the taskbar.
Nothing in My Computer.
Checked under drive management and it was there, working - and set as G.
Odd, as that was already mapped to a network drive.
Opened My Computer, double clicked G and lo & behold, there's my USB pen. Obliterating my drive mapping. Removed the pen, and it was back to my network drive.
Some real weirdness going on, I'm sticking with it as I can't be bothered with the downtime on this system (it's an imaging server) but I've submitted a bug report through technet to MS anyway to cover bases.
I've remapped my network drive for now anyway, just thought I'd share some more issues.
Lets see what happens with it and I'll post another link direct from MS as and when it's fixed. Of course, neither I or Freddyshouse take responsibility for buggering up your computers
(But either way, I apologise for advising installation of it).
I'll only ever link to MS for MS updates for safety & trust reasons and even then that doesn't guarantee quality as we now know