Actually, I looked. And it's not, according to the USCCB Liturgical Calendar...and the Archdiocese of Washington (Msgr Pope's diocese) definitely hasn't transferred it. (in fact, I'm getting ready to leave for Mass as it is a Holy Day of Obligation in ADW)
To access Liturgical Calendars on USCCB website (BCL Documents), Click Here. * Whenever Jan 1, the solemnity of Mary, Mother of God, or Aug 15, the solemnity of the Assumption, or Nov 1, the solemnity of All Saints, falls on a Saturday or on a Monday, the precept to attend Mass is abrogated + The solemnity has been transferred to this date. ++ The Bishops of Province VIII, which includes the Diocese of Rapid City, have decided that the Ascension will be celebrated on the 7th Sunday of Easter.
I'm going so it doesn't matter.