I have booked mine but may have been a bit hasty with it
I got a direct virgin flight to Las Vegas return for £760 through dial a flight
After a bit of battering between them and the flight centre
Going out from heathrow @ 11am on 23rd arrive Las Vegas 9am on the 23rd
Just thought this may help as a comparison for people to use when booking.
And may even get you a better deal in wich case you can share your savings and get me a pint at the airport bar
Hope it helps let me know what happens good luck
Stan