Steam's library is finally getting its long-awaited makeover! The new library is available now in public beta. You can join the beta on Steam's website.You'll need to update you client and select Steam Beta Update in the Beta Participation menu of the Account tab. You can now access the the bright new library and its new overviews.
The browsing experience is clearly improved, but there's still some work to be done. It's a good first update for the new Steam library, and you can contribute alongside the community and developers by giving your opinion on this public beta.
You can find the detailed instructions on how to install Steam Library Beta and more information on the new features in Steam's blog.