If Rome wasn't built in one day, I certainly can't expect Stock Advisor pick eBay (NASDAQ:EBAY) to build a social network in two. However, my first impression as I strolled past one vacant community after another in eBay Neighborhoods is that it sure hurts to get pelted with rolling tumbleweeds and swirling ghost-town dust.

"Your timing is impeccable," reads the introductory page on way too many of the niche-specific sites that make up eBay Neighborhoods. "Be the first to start a discussion."

If you haven't checked out eBay Neighborhoods, you might as well. The design is slick. The community aspect might be lacking, but eBay has years of experience and consumer-generated content to populate individual neighborhoods with a ton of merchandise, blogs, guides, and product reviews.

Some of the stylistic touches will give you goose bumps -- the good kind. Visit a neighborhood, and check out the "Related Neighborhoods" box to the left. Hover over one of the iconic photographs, and they come out of focus to reveal the neighborhood as the surrounding icons blur. It's sheer genius -- a nod to what eBay's team can do when it's given a wide enough canvas.

So where are the people? The top dog as of last night was the Coffee Lovers neighborhood, which had 291 java junkies on board and 86 posts. The second largest neighborhood -- Jewelry -- has less than half as many members.

Dig deeper, and you'll find even big brands -- ones that you'd think would be huge draws -- are off to slow starts. Barbie, Mattel's (NYSE:MAT) doll that has amassed countless collectors over the years, has just two members on board.

"Wow," writes the first -- and only -- member to post a comment on the discussion board. "Am I the first???"

You're the first, all right. That Tuesday night post is also the last, so far.

Apple (NASDAQ:AAPL) is a brand that Mac-heads can get pretty passionate about, right? Well, on eBay, its neighborhood has just six posts from its 56 members.

Rebuilding the neighborhood
I see the logic in building communities around products. It gives eBay the perfect opportunity to showcase the items on the bidding block in a particular category. Meg Whitman is no dummy.

But those groovy, expandable thumbnails at the top right of every eBay Neighborhoods page -- is that the killer app? And when you get past the eye candy, you see that the only real opportunity for members to socialize is in the discussion board itself. If that was all that existed at social networks such as Facebook, News Corp.'s (NYSE:NWS) MySpace, and Google's (NASDAQ:GOOG) Orkut, they'd sink like bricks in Web 1.0 wrappers. As it stands, eBay Neighborhoods is little more than a collection of slick-looking message boards and a simple photo-sharing platform with a lot of distractions around the edges.

That may not be a bad thing, but you want to know what would flesh out these Neighborhoods quicker than the California gold rush? Feature the community members' listed items on eBay, above the thumbnails of every other related item available on the site. That would give sellers a bigger incentive to participate in eBay's little social experiment. Once everyone is chatty, it may increase sales within each neighborhood as folks become more familiar -- and trusting -- of the virtual citizenry.

And how do you turn lurkers into participants? That's easy. eBay knows the value of its own feedback system. It has seen point-based reward programs take off with Yahoo! (NASDAQ:YHOO), for Yahoo! Answers, and community-voted post ratings have worked for sites such as Amazon.com (NASDAQ:AMZN).

If virtual carrots don't work, then eBay should swing for the fences. Offer community members a single day of free -- or sharply discounted -- listings on the related category. That would be a dinner bell worth ringing, especially if the community begins discussing the related items they put up for sale.

So raise the stakes, eBay. You've got a pretty canvas. You've got lovely colors. Don't settle for painting in broad strokes. If you want everyone to attend the block party, you have to create a vibrant neighborhood full of things to do.

In the Foolish neighborhood:

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Longtime Fool contributor Rick Munarriz is a satisfied eBay user, with 172 positive feedbacks to show for it. He does not own shares in any company in this story. He is also a member of the Rule Breakers analytical team, seeking out the next great growth stock early in its defiance. The Fool has a disclosure policy.