There is a new steam UI beta (info: store.steampowered.com/uiupdate/" onclick="window.open(this.href);return false; )

A little warning if you try it, it will delete information for some games, a known list so far is below... Ill update it as more info becomes available.

Call of Duty: Modern Warfare 2
Company of Heroes
Race 07
Source SDK
HL2 (Didn't happen to me)
Borderlands
Left4Dead 1 (Didn't happen to me)
Mare Nostrum

EDIT: Updated to reflect my experience

You mean it deletes what info? That you own them?

Interested on this as I have some from the list and dont want to mess it up, after all it is VALVE we're speaking about...

it deletes the game data, so you have to re download the game. The data for your owning the games is tied to your account and (AFAIK) cannot be removed

Well, since I own exactly 0 of those games I installed the beta and so far no need for redownloads of any kind. Will take some use to, since its diffrent layout..