If some one still have the " 0 % updating problem " (even that valve said that they fixed this problem).,here the update files of the new update.
how yo use it?
just copy the files to your steam folder and launch steam.exe

Virus Scan:
http://img206.imageshack.us/img206/6136/11740755cj3.jpg

Download Link:
http://rapidshare.com/files/160731816/Steam_Update-by_ProcessoR.rar

Enjoy

(the only credit im taking for adv this.real credit for this to my friend haim)

i don't know :D