Note sure if already posted. Might be targeted.

Fly between the U.S. and London Heathrow in United First, United Business or Continental BusinessFirst and earn up to 150,000 bonus award miles.
Earn up to 150,000 bonus award miles when you fly to London
Book qualifying round-trips on United®, United Express®, Continental® or Continental Express® from the U.S. to London Heathrow in F, J, C or D booking codes and earn big.
First roundtrip: Earn 25,000 bonus award miles
Second roundtrip: Earn 35,000 bonus award miles
Third roundtrip: Earn 45,000 bonus award miles
Fourth roundtrip: Earn 45,000 bonus award miles.
Register before you travel at www.united.com/offer/MPI051.Fly between September 28th 2011 and December 31st, 2011. Hurry, book your travel today.
Registration required. Offer may be earned once for a maximum of 150,000 bonus miles.
Terms and conditions