“Come and see what we’re building.”

Those words — constituting the whole of a Facebook (NASDAQ:FB) event invite last Wednesday — sent the Web abuzz and FB shares up 5%.

Well, Wall Street saw what Facebook is building … and right now, it doesn’t look impressed.

Facebook announced the launch of “Graph Search,” which will allow users to search for things within the parameters of their friends and other interests. Graph Search will be a text box at the top of each page where users can search for people, photos, places and interests, and answers will be based on factors such as “likes.” It’s currently in beta testing, but will be rolled out slowly to investors in the U.S.

So, the name isn’t catchy, but it does have plenty of potential. Facebook is the ultimate source of Big Data, and eventually could take search to a new level. Immediately, the most interesting aspects of Graph Search are how thinly it can splice the information — which would be interesting to advertisers — and how it could connect people with local businesses, which should be a nice way to monetize mobile.

That said, investors’ immediate reaction was muted, with FB shares dropping off 1.5%. However, Yelp (NYSE:YELP) shareholders might be taking it seriously — while the company lost some ground at the beginning of the day, shares have slid further after the announcement and are more than 7% in the red Tuesday.

If there’s any worry about potential pressure on Google (NASDAQ:GOOG), the stock isn’t showing it — GOOG shares are up 0.5% as of this writing.