Y Combinator grad Hipmunk—the all-you-can-eat buffet of travel sites—just got a bold new vote of confidence from IVP and existing investors in the form of a $15 million Series B round.  As CEO and co-founder Adam Goldstein explained in the company’s blog: “we need to go big or go home.”  The new round brings IVP’s Todd Chaffee on as a new member of the board of directors.  Series A investors Ignition Partners also joined in the round.

“We led the $15 million round in Hipmunk because they have a truly innovative product offering targeting the huge online travel market,” IVP General Partner Todd Chaffee told me.  “They have an incredibly bright, young management team that will continue to deliver breakthrough products that vastly improve travel experiences for both leisure travelers and business travelers around the world.”  He added: “We believe they can eventually become the dominant player in this space.”

Launched in August 2010, the almost-two-year-old startup has made some impressive strides.  In October of last year, the company added Google Calendar integration to help you book flights in accordance with your busy, busy schedule.  In January it launched a hotel search feature for its iOS and Android apps.  And the startup that originally launched as a two-man company has now grown to 16 employees.

Goldstein says that the new funds will be used to hire more engineers so that the company can build new products simultaneously instead of one-at-a-time, as it’s done before.  It also plans to ramp up business development and marketing to drive more partnerships and awareness.

“We met Todd a while back as he was always a big fan of our product and our team. He’s a top-notch investor having made incredibly successful investments in both the travel and tech space,” said Goldstein in a blog post.

Chaffee has indeed made some pretty noteworthy investments in companies like Twitter, HomeAway, LivingSocial, Netflix, comScore, and Yahoo, among others.  His interest in Hipmunk heralds good things to come.  Adam Goldstein says to be on the lookout for upcoming announcements from the company over the next few months.