Chamath Palihapitiya is the founder of The Social+Capital Partnership. He spent 5 years working at AOL, most recently being the General Manager of AIM and ICQ. Chamath also joined Facebook from The Mayfield Fund. Recently, Chamath was asked whether he wanted to participate in Airbnb’s latest round of funding, but he was concerned that the $112 million in funding was for founder cash-out and control. Below is the full letter from Chamath [AllThingsD]:

Centrify has announced that they have raised $16 million in Series D. They plan on using the funding for international expansion and continued revenue growth. Centrify provides security and compliance for on-premise and cloud-based systems. Centrify also provides applications to over 3,500 customers. Investors in this round include the Mayfield Fund, Accel Partners, Invesco Private Capital, and Sigma Partners.

Couchbase, the NoSQL database company created by the merger of CouchOne and Memebase, has raised $14 million in new funding. The investors include Ignition Partners, Accel Partners, North Bridge Venture Partners and Mayfield Fund. The Series C funds, which bring the company’s total to $30 million, will be used to grow Couchbase’s enterprise and help the company expand internationally. [TechCrunch]

Brighter.com is a website that allows people to compare dentists based on reputation and price. Brighter.com has pre-negotiated prices on all major dental procedures at over 25,000 dentists across the nation. Brighter.com collects patient reviews from members and Yelp. Brighter.com raised $5 million in Series A led by Mayfield Fund.

Tagged is a San Francisco based social network that has ended 2010 with 100 million registered users and they have hit its third year of profitability. This also means that Tagged has more users than LinkedIn, but less than Facebook and Twitter. Tagged made over $32 million in revenue and their virtual currency revenue is up 71% since 2009. Tagged plans to double their staff and give all employees a 10% raise. Investors in Tagged include Mayfield Fund, Horizon Technology Finance, and Leader Ventures.

The Rubicon Project is an ad optimization company based in Los Angeles, California. The company has raised $18 million in funding and they acquired the Fox Audience Network (FAN). After this round of funding, it brings The Rubicon Project’s total funding to $60 million.

PlayFirst is a popular mobile gaming company behind games such as Dinner Dash, Cooking Dash, Wedding Dash, and Hotel Dash. These games have been extremely popular on the Apple App Store. Because of this, PlayFirst raised $9.2 million in venture capital funding. PlayFirst plans to use the funding to increase their agility in the social and mobile gaming space according to VentureBeat. Mayfield Fund, Trinity Partners, DCM, and Rustic Canyon Ventures put in $5.2 million in this round. Comerica Bank invested $4 million in debt financing.

Alphonso Labs is a Palo Alto based company that created an application called Pulse. Alphonso raised $1 million in seed funding from Redpoint Ventures, Greycroft Partners, Mayfield Fund, and Lightspeed Venture Partners.