Matin Maulawizada, a makeup artist based in New York, used to spend hours prowling department stores’ beauty floors to find out what was new and noteworthy. Now, Mr. Maulawizada, the global artistry director for Laura Mercier, likes to log on to Pampadour.com, a sleek new beauty-focused social network, to see what products colleagues are using — or, in the company’s parlance, “pamping.” “It really saves me time,” Mr. Maulawizada said.

Quietly introduced at the end of February, Pampadour says it has already signed up more than 3,000 users, many of them beauty professionals. The site has joined a small but growing number of social platforms that allow members to tag and review cosmetics with others in their network, potentially shifting power from traditional retailers.
Among them are Bloom.com, which has accrued about 250,000 members since it started in August 2011. Like Pampadour, Bloom allows users to upload pictures of hair, makeup and nail looks they’ve created, as well as tag the products they’ve used in those looks. But Bloom, which boasts a database of 50,000 products from 700 companies, is also able to direct members to Web retailers where some of those products may be sold.