Just got this on email...
"Earn up to 20,000 Bonus Dividend Miles when you fly to Europe this summer with
this exclusive offer from US Airways.
-Looks like it's only good to London, Manchester, Frankfurt and Brussels.
And of course...the stipulations:
* Terms and Conditions: 20,000 mile bonus is valid with the purchase of an
unrestricted First or Envoy Class ticket (F or J fares); 10,000 mile bonus is
valid with the purchase of an unrestricted Coach Class ticket (Y or B fares);
5,000 mile bonus is valid with the purchase of a discounted Coach Class ticket
(M or H fares). Offer requires the purchase of a transatlantic, roundtrip (2
segments) ticket on US Airways for flights to/from London, Manchester, Frankfurt
and Brussels with travel valid between May 16 and July 31, 2001. Registration
for this offer (Bonus Request # 2321) is required prior to departure. This
offer may not be combined with any other Dividend Miles offer or promotion
except the online booking bonuses available through usairways.com. Bonus miles
will be credited within two weeks after completion of travel. Only the original
recipient of this e-mail is eligible for this offer.

Are these Tier miles. I read the info on the USAir site, and cannot tell if they are, or not.

Promotional bonus miles usually don't count towards tier status.

The standard 50% class of service bonuses do count when you upgrade from a B/Y to J or F.