During the last update I attempted to start Steam, and I received an error message
But then program seems to load alright.
I ran steam in command line to see if there were any errors

Running Steam on ubuntu 12.04 64-bit
STEAM_RUNTIME is enabled automatically
tar: steam-runtime/COPYING: Cannot utime: Operation not permitted
tar: steam-runtime/scripts/check-program.sh: Cannot utime: Operation not permitted
tar: steam-runtime/scripts/fix-debuglinks.sh: Cannot utime: Operation not permitted
...
...
tar: steam-runtime/i386: Cannot change mode to rwxr-xr-x: Operation not permitted
tar: steam-runtime: Cannot utime: Operation not permitted
tar: steam-runtime: Cannot change mode to rwxrwxr-x: Operation not permitted
tar: Exiting with failure status due to previous errors
Unpack runtime failed, error code 3
Error: Couldn't set up the Steam Runtime. Are you running low on disk space?
Continuing...

and every unpacked file in the runtime gave the tar error.

I checked just to make sure it wasn't a disk space problem

>df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/sdb1        66G   30G   33G  47% /
/dev/sda3       772G  646G  127G  84% /media/Storage
/dev/sda2        96G   67G   30G  70% /media/Windows
/dev/sda5        56G   16G   37G  31% /media/Linux_partition

One caveat I have though.
I have my ~/Steam file symbolically linked to a ntfs storage partition, which i know has permission problems occasionally.
So I changed the link to point to a copy of the Steam folder in an ext4 partition, and ran it again, without any change in the error message.

EDIT
it seems that I DID had a problem with my ntfs permissions.
I was not mounting pointing at the right user.

after remounting with the correct permissions, and changing my /etc/fstab the error was resolved
I'm not sure why I continued to have the errors with my ext4 partition, but all is well