I should also add, the recent Halloween 7s event held in St Peterburg, Florida was a test event for the American Rugby 7s group. They are planning to launch a Pro Sevens circuit in the US. The event was primarily set up to show off to potential investor in regards to product and they put on a pretty high quality event in terms of standard of play. You had essentially the Argentine 7s team (who won the tournament), the Canadian Men's 7s squad, two teams splitting the Eagles 7s OTC group (Hawks and Falcons) plus a team from Utah, Denver, New York and Ohio.
In terms of their window. Some say 2016 other think 2017 is more realistic.
As for United World Sports and their Super 7s concept (for those unfamiliar with this, it's 7s played over 4 12 minute quarters with unlimited interchange and game day squads of 21 players) that is attempting to formalize the game for a league structure, have entered the investor cycle. They are attempting to raise $40 million dollars. Hell, of a figure.