@Unique17 The listing looks genuine and the host does have a verified profile with a review (as a guest). But with a brand new listing, risk is higher that the booking might get canceled - for example, if the house gets trashed by a big party the night before you arrive. It's hard to tell how committed an untested host will be to fulfilling Airbnb bookings.
Personally, I'd find it too risky to book an unreviewed listing with a large group, since it would be really hard to re-house everyone if the stay doesn't work out. But some correspondence with the host would at least give you an idea of whether he's ready for prime time.