The founder of Priceline is introducing this new concept. He is advertising like crazy so eventually it worked, and I checked it out. He is working with OMAAT and
here is the post.
Also,
this.
The interesting part to me;
Wouldn’t it be cheaper just to book everything separately?
Yes and no. Upside will show you the exact flights in your itinerary, so you could always go an book those on your own.
Many of the hotel rates Upside has access to will be the result of negotiated deals. You may not save much (if anything) by trying to book those same hotels.
I'm not a biz traveler but would be interesting to see if one of their packages can save me $ with the guaranteed $150.
I doubt it though