This is from an Orthodox site, but it gives a bit more defination. Also the East apporaches things just a bit different, but yet the same…
On the Feast of the Dormition…
Dormition of the Theotokos
…Once, when She went to the Mount of Olives to pray, Archangel Gabriel appeared and spoke of Her approaching departure from this world. Upon returning home, She told Apostle John all that the Archangel had said to Her and started preparing Herself for Her final day on earth. Friends and relatives gathered, and eleven of the apostles were miraculously transported from various parts of the world to Her deathbed. They were all amazed to see each other there. When Apostle John explained that the Mother of God would soon be departing this world, they understood why God had brought them together and became sad. But She comforted them, saying: “Do not cry and darken My happiness with your sadness. I am going to My Son and your God, and you will bury My body and return each to your work.” As the time of Her death neared, the room shone with a divine light, the roof disappeared, and a wondrous sight appeared before all: the Lord Jesus Christ descended from heaven surrounded by many angels. All looked upon this wondrous sight with awe and reverence, and when they approached Her bed, the holy body of the Mother of God shone radiantly, and a fragrance of incense pervaded the room.
The apostles carried the body of the Mother of God through the city to Gethsemane, to be buried at Her request in the tomb of Her family and Joseph. They buried Her body, closed the tomb with a stone and remained there at the site in prayer for three days. On the third day Apostle Thomas arrived and was very saddened that he did not find the Mother of God alive. To make him feel better, the other apostles rolled away the stone to let him pay his respects to the body. But on entering the tomb, they found that the body was not there – only the winding sheet. They returned home to partake of a communal meal at which they always left a place for the Resurrected Lord. After the meal, they raised the bread left for Christ aloft and exclaimed: “Lord, Jesus Christ, help us.” And they heard a choir of angels, and when they looked up they saw the Holy Virgin surrounded by angels. She greeted them, saying: “Rejoice, for I am with you through all the days.” Then the apostles were filled with joy, and instead of using the usual words, they exclaimed: “Most holy Mother of God, help us.” And now they understood and believed that upon the third day after Her dormition, the Mother of God had been resurrected.
Thus, the dormition of the Mother of God is not a sad event, but a joyous one.** Her death is but a short sleep, after which follows Her resurrection and ascension to heaven**. From the very beginning, the Church saw in the Mother of God the One who would pray for all of mankind. She is the haven of all the mothers in the world. She teaches us how to live in total faithfulness to the will of God. She, who kept in Her heart the divine words, is an example of faithfulness, love and service.