Groupon Getaways with Expedia will launch in June with hotels in the US, expanding to airlines and car rentals, even cruises. Before the end of the year the service will roll out to Latin America, Europe and then Asia. It'll work a lot like Groupon — customers will have a limited time to buy a discount voucher, usually about half-off, for future travel. They'll be able to redeem the voucher within a certain redemption period, but the idea is that the period will be flexible, without blackout dates.

Together Groupon and Expedia will be able to reach a huge audience — 50 million people between Groupon and Expedia's members.

Who wins on the back end? The merchant will receive about half of what consumers spend, Expedia and Groupon sharing the rest. The companies didn't disclose any specific terms but Durchslag says Expedia isn't doing any deals that aren't accretive. This is certainly a crowded marketplace with the likes of Priceline,but Groupon and Expedia hope that the simple, straightforward approach will cut through the clutter.