Holy Days of Obligation 2011 in USA?

What are the Holy Days of Obligation for the year 2011 in the USA?
Is there a list with all the Holy Days in the Catholic Church?

I ask because I thought Ash Wednesday was a Holy Day of Obligation but I've been told it's not.
I was surprised to find out about that because the church has always strongly advised attendance at mass on that day.
Can anyone please post the complete list of Holy Days of Obligation in the United States?

Holy Days of Obligation are feasts on which Catholics are required to assist at Mass.
Serious reasons excuse us from these obligations.
This is the official list of dates of the Holy Days of Obligation in the USA for 2011.

Mary, Mother of God (Saturday, January 1, 2011)
Ascension (Thursday, June 2, 2011)
Assumption of Mary (Monday, August 15, 2011)
All Saints Day (Tuesday, November 1, 2011)
Immaculate Conception (Thursday, December 8, 2011)
Christmas (Sunday, December 25, 2011)
Every Sunday of the year.

The Holy Week is spiritually, the most important week of the the entire Liturgical year.