YouTube has begun the first phase of a redesign that will highlight its gradually expanding library of premium shows and movies. YouTube has announced that it will expand its library of full-length movies and TV shows, in addition to launching a new advertising service and adding about a dozen new content partners.

The company hopes to add to its movie and show content over time but some titles offered for free include "Beverly Hillbillies" and "Married With Children," and hundreds of movies, including "Casino Royale" and "Cliffhanger."

Navigational changes include the introduction of two new tabs -- "shows" and "subscriptions" -- to YouTube's masthead. Meanwhile the site has dropped a "Community" tab, which included contests, events, and groups. 

The changes are motivated largely by the need to enhance YouTube's appeal to advertisers, and to increase the available quantity of its preferred video format: in-stream ads. Advertisers can bid on this inventory through the Google TV Ads program, which has been expanded to offer both broadcast and online ads. 

Initially YouTube was to roll out the new site design the first week of April, but the date was pushed back for unknown reasons. 

While agencies are by and large excited about the new design, content freshness remains an issue. Movies and TV shows available now include mostly older fare from CBS, MGM, Sony, and other partners. Current films and series are markedly absent.

Google has hinted it's close to signing new licensing contracts for long-form programming.

YouTube has already partnered with several other studios, whose parents include Sony Corp., Lions Gate Entertainment Corp., CBS Corp., Metro-Goldwyn-Mayer Inc. and Liberty Media Corp.

The company announced new partnerships with 13 smaller companies such as Discovery Communications Inc., National Geographic and SnagFilms LLC.

Officials said that certain content providers will also provide their own video players, such as Sony's Crackle.com player, which will be embedded in the YouTube site.