I got this UA promotion email today:

Dear nermaljcat,

Thank you for registering for this promotion to qualify for 2008 elite status faster. For a limited time, you can earn an additional 50% Elite Qualifying Miles/Elite Qualifying Segments (100% total bonus) on flights in United First (F, A, P), United Business (C, D,Z) and full fare United Economy (Y, B). Offer is valid for travel through December 15, 2007.

Valid routes to earn this EQM/EQS bonus are to/from*:
Washington D.C. (IAD) - Los Angeles (LAX)
Washington D.C. (IAD) - San Francisco (SFO)
Washington D.C. (IAD) - Las Vegas (LAS)
New York City (JFK) - Los Angeles (LAX)
New York City (JFK) - San Francisco (SFO)

If they can't beat prices and service, they try to lure you with a carrot of 50% bonus EQM (but only for the more expensive fares). I'd prefer Virgin over UA on any route they fly. Hopefully it will be SFO->JFK next month.

Funny thing is that I can't remember registering for this promotion..

United used promotions of this sort to compete against Independence Air. In the end, it worked. I suspect VX is better financed for its fewer chosen routes, however. This one looks quite selective, aimed only at keeping premium cabin business.