This is possibly targeted – but worth a shot anyways.

Update your member profile today and earn 1,000 bonus award miles

Dear MilesQuest,
As a valued Mileage Plus® member, you should be the first to know about opportunities to earn award miles, partner offers, fare sales and more. The easiest way to get the inside scoop is to update your Mileage Plus member profile and choose to receive emails from Mileage Plus and United®.

Update your profile today and earn 1,000 bonus award miles in the process. It’s the first of many exclusive offers you can look forward to.
Earn 1,000 bonus award miles when you:

1. Visit My Profile on United.com
2. Login to your account
3. Choose “Mileage Plus Communications” and “United Offers & Announcements” in the Email subscriptions section

Don’t let another bonus award mile offer pass you by and earn 1,000 bonus award miles today.
Your Mileage Plus team

1. This offer is valid only for recipients of this mailing, and you must be a Mileage Plus member to participate in this offer.
2. To earn 1,000 bonus award miles, members must provide a current valid email address at United.com/myprofile and remain opted in for the following email subscription categories through February 28, 2011: Mileage Plus Communications and United Offers and Announcements.
3. Bonus award miles can only be earned once for each Mileage Plus account and will be posted three months after your email profile is updated.