– Connie Loizos is a contributor to PE Hub, a Thomson Reuters publication. This story originally appeared here. The views expressed are her own. –

Airbnb is on a tear. Three years after the San Francisco-based company began inviting real people to list for rent their homes and apartments, castles and houseboats, users have booked 1.9 million nights in more than 184 countries; bookings are growing an astonishing 40 percent month over month; and roughly 1,000 new properties are entered into its system each day.

The company is growing so fast, in fact, that it’s reportedly raising $100 million at a whopping $1 billion valuation — a mighty addition to the $8 million in capital it has previously raised from Sequoia Capital, Greylock Partners, and numerous individuals.

Unfortunately for Airbnb, all the hype has captured the attention of the Samwer brothers, who’ve famously created a number of successful clones. Indeed, just two weeks after rumors of Airbnb’s massive fund-raise surfaced, the Samwers’ months-old European clone, Wimdu, announced it raised $90 million.

Considering that the majority of Airbnb’s business comes from Europe, one might consider the development troubling. But Brian Chesky, Airbnb’s 28-year-old CEO and co-founder, said he doesn’t think that it “changes things much. We were always expecting some competition. We just have to grow as quickly as possible.”