Eek latest pacman -Syu has broken my Arch64!

Question

I'm not *sure* but when I came in to work this morning, I did the usual pacman -Syu that I do each morning. (pacman.log exerpt below)
binutils (2.17-1 -> 2.17-2)
coreutils (6.4-2 -> 6.5-1.1)
libcups (1.2.5-1.1 -> 1.2.7-1)
cups (1.2.5-1 -> 1.2.7-1)
gcc (4.1.1-3 -> 4.1.2-1)
warning: extracting /etc/locale.gen as /etc/locale.gen.pacnew
glibc (2.4-4 -> 2.5-2)
pciutils (2.2.4-1 -> 2.2.4-2)
And thought nothing of it, until I tried to use 'firefox' later on in the day, now 'firefox' can't be found  (-bash: firefox: command not found )
But Pacman still thinks its there:
[root@garfield bin]# pacman -Q firefox
firefox 2.0-1
Which is err odd...and far far worse than that :
[root@garfield bin]# cd /usr/bin
[root@garfield bin]# ls
Segmentation fault
[root@garfield bin]#
I'm not saying it *was* the upgrade, but I've done nothing else this morning that could have caused this, eek!!
Any ideas gratefully received!

Answer 1

That works perfectly! ls works again, and firefox is 'firing' up again, 'woot'.  Next question, err how'd that happen then!