In selective tests with users, Yahoo is showing off a redesigned home page that sports a more streamlined look and a revamped left navigation bar that lets users add links to external sites such as WSJ.com, NPR.com and Style.com.

The upgraded version, glimpsed Friday as part of ongoing testing that Yahoo is conducting, reflects the Web portal's strategy to open up more to third-party sites and developers to better compete with the likes of MySpace and Facebook.

In that vein, the biggest change is the customizable left nav bar featuring Yahoo properties that now allows people to add or edit links to outside sites through an "application gallery" that opens up via tabs at the top and bottom of the section.

The gallery displays clickable icons for a group of more than 20 third-party publishers that also includes MySpace, Barron's, Divine Caroline, and MarketWatch. It seems likely that Yahoo will add more sites to this initial group of partners, but it doesn't appear at present that Yahoo allows users to add links to any other site in the nav bar.

In its revamped home page launched last fall, AOL appeared to go farther with its competing open strategy by letting users add links from any site to the left nav bar. The "My Networks" section on the AOL home page also more prominently features access to social networks including MySpace, Facebook and Twitter.

Links to outside email services, including Yahoo Mail and Gmail, are also better showcased on AOL through large icons in the top corner of the screen.

Tabs alongside Yahoo and other properties in the nav bar open up windows that allow users to get quick hits on things like stock quotes, sports scores and weather without having to click through. The windows also carry display ad units and links that drive users to articles within the Yahoo network.

Among other key changes, the new Yahoo home page has a cleaner, more visually appealing design, with larger images accompanying top news stories at the top-center of the screen. Here, Yahoo also appears to emulate AOL by featuring a rotating set of stories that users can scroll easily across to select from.

"Top Searches" has also been pushed up from the bottom right corner of the page to the top right, suggesting that Yahoo may not be so eager to outsource its search business after all. In any case, they want to showcase it better.

As far as advertising, the standard display box on the right appears unchanged from the current version (dubbed "Classic Yahoo.com on the new site), with the same ad for the new movie release "Ghosts of Girlfriends Past," running simultaneously on both versions.

Gone from the new site, however, is the Marketplace section, which included text links on the home page and pushed users to Yahoo Shopping. A link to Yahoo Shopping has also been removed from the nav bar, indicating that the company may be pulling back on promoting its e-commerce-related efforts.

A Yahoo spokesperson Friday said Yahoo is testing several versions of the new home page with small "buckets" of its users and that the timing of the formal relaunch had yet to be determined. "We haven't finalized what the final product will look like," he said.

In a post on the Yahoo blog last February, the company said it had started "bucket testing" the new home page last fall, beginning in the U.S., U.K., France and India.

During Yahoo's first-quarter conference call on April 21, CEO Carol Bartz mentioned that the new home page was in the works but did not offer further details. However, she stressed that the company wants its Web properties to have a consistent look and feel across the network and around the world. To that end, Yahoo plans to "globalize" its properties to ensure a uniform user experience.

Under Bartz, Yahoo has also accelerated steps to shut down underperforming properties such as GeoCities, the early community-focused service that was overtaken by the blogs and social networks it helped give rise to.

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