Here is who attended per the official documents. I'll add stories for each group as they become available.
His All Holiness BARTHOLOMEW (Ecumenical Patriarch)
His Eminence Metropolitan GENNADIOS
His Eminence JOHN (Metropolitan of Pergamon)
His Eminence Metropolitan TARASIOS
Mr Karlos Irakli TARINAS
Greek Orthodox Patriarchate of Alexandria and All Africa
His Eminence Archbishop SERAPHIM
Greek Orthodox Patriarchate of Antioch and All the East
His Eminence Metropolitan SILUAN
Russian Orthodox Church
His Eminence Metropolitan HILARION
His Excellency Bishop SERGY
Patriarchate of Georgia
His Eminence Metropolitan GERASIME
Reverend Father Gia ZVIADADZE
Reverend Father IOANE
Serbian Orthodox Church
His Eminence Metropolitan AMFILOHIJE
Protopresbyter Obren JOVANOVIC
Protodeacon Igor BALABAN
Patriarchate of Romania
His Eminence Metropolitan IOSIF
His Grace SILUAN
Revd Deacon EFREM
Orthodox Church of Cyprus
His Eminence Metropolitan NIKIFOROS
His Eminence Metropolitan ISAIAS
Orthodox Church of Greece
His Grace Bishop DIONYSIOS
Most Reverend Archimandrite IGNATIOS
Orthodox Church of Albania
His Eminence Metropolitan JOHN
Ukrainian Orthodox Church
His Eminence Metropolitan PLATON
His Eminence Metropolitan ANTONIY
Revd Archimandrite FILIPP
Orthodox Church in America
His Eminence Metropolitan TIKHON
Revd Father Eric TOSI
Russian Orthodox Church
(mospat.ru) - On 18 March 2013, a delegation of the Moscow Patriarchate headed by Metropolitan Hilarion of Volokolamsk, chairman of the Moscow Patriarchate’s Department for External Church Relations (DECR), arrived in Rome to attend the enthronement of Pope Francis. The DECR chairman and Bishop Sergiy of Solnechnogorsk, head of the Moscow Patriarchate’s Administrative Secretariat were met at the airport by the Rev. Milan Žust of the Pontifical Council for Promoting Christian Unity and hieromonk Antoniy (Sevryuk), rector of the Church of St. Catherine in Rome and secretary of the administration of the Moscow Patriarchate’s parishes in Italy.
Members of the delegation were accommodated at the House of St. Martha, where the new Pope is residing. A short meeting with Pope Francis took place at the refectory. The Pope warmly greeted Metropolitan Hilarion who introduced members of the delegation and conveyed cordial best wishes to Pope Francis from His Holiness Patriarch Kirill of Moscow and All Russia. The Pope said that he had offered special prayers for Patriarch Kirill at the divine service as it is a commemoration day of St. Cyril of Jerusalem according to the Julian calendar. He thanked Metropolitan Hilarion for the exhibition of Russian icons held in Buenos Aires last autumn with the St. Gregory the Theologian Charity Foundation’s assistance. The future Pope visited the exhibition and keeps warm recollections of it.
The DECR chairman greeted other guests who arrived in Rome to attend the enthronement: Patriarch Bartholomew of Constantinople, Metropolitans John of Pergamon and Emmanuel of France (Patriarchate of Constantinople), Amfilohije of Montenegro and the Littoral (Serbian Orthodox Church), John of Korça (Albanian Orthodox Church), and Cardinal Christoph Schönborn, Archbishop of Vienna.
Attending the enthronement of Pope Francis as honorary guests will also be Metropolitan Anthony of Borispol, chancellor of the Ukrainian Orthodox Church, and Metropolitan Platon of Feodosia and Kerch, who served in Argentina during many years and was well acquainted with the new Pope.
Orthodox Church in America
(OCA) - As word comes in from Metropolitan Tikhon or Father Eric we’ll update you, but already we have a few of Father Eric’s photos sent earlier this morning from Rome. In the meantime, I was up at 4:30 a.m. to watch the CNN coverage of the inaugural Mass from Saint Peter’s Square. 100,000-200,000 worshippers and pilgrims from around the world, political leaders (including VP Joseph Biden), representatives of other religions and churches. Some 500 priests distributed communion to the crowd. During the Mass Pope Francis exchanged the kiss of peace with Ecumenical Patriarch Bartholomew and Armenian Catholicos Karekin II. I caught a glimpse of Metropolitan Tikhon standing with the other Orthodox bishops in a section next to the vested concelebrating Roman Catholic cardinals and bishops.
The Pope’s sermon after the Gospel (Matthew 1:16, 18-21,24a, read in Greek)—for the feast of Saint Joseph “the betrothed” emphasized Joseph’s role as protector, and drew out the message that we are all called to be protectors, custodians, stewards of one another, especially of the weakest among us and God’s creation (a theme that would resonate well with Patriarch Bartholomew, known as the “Green Patriarch” for his dedication to care for the environment.) He also spoke of protecting our hearts—fitting for the spiritual effort of Great Lent—since this is where actions good and bad have their seeds and take root.
At the close of the outdoor Mass, Pope Francis went back into Saint Peter’s Basilica and prayed before the tomb of Saint Peter, the first Bishop of Rome. Whatever differences still exist between us, it is gratifying to see Orthodox and Catholics coming together around the apostolic faith in the crucified and resurrected Lord Jesus Christ, whom Saint Peter witnessed, preached and died for.