Who will Arsenal face in the CL?

The CL draw will take place today. The choices are Fiorentina, Atletico Madrid, Celtic FC, RSC Anderlecht, and FC Timisoara. So who will it be?
Fiorentina: The Violas were in the news recently with a possible Felipe Melo transfer to Arsenal which fell through. He eventually went to Juve. The club finished fourth in the Serie. They have Adrian Mutu who was recently ordered by CAS to pay €17.17 million to Chelsea as compensation. Mutu came to the Blues from Parma on a record €29.4 million transfer fee. He was terminated from Chelsea and banned from football for 7 months after he failed a drug test for cocaine. Mutu and Gilardino have formed quite a partnership with 33 goals scored last season. With Riccardo Montolivo, a Lippi favourite, Fiorentina are a threat. They met each Arsenal in the 1999 group stages and won through a Gabriel Batistuta goal.
Atletico Madrid: They were beaten 2-1 recently by Arsenal in the Emirates Cup on the strength of two Arshavin goals but showed some spark with a German Pacheco equalizer. Ex-Arsenal winger Jose Antonio Reyes was part of the squad. The team was under strength without Pichichi winner Diego Forlan. They finished fourth in the Liga on the strength of his 32 goals. Apart from Forlan and Reyes, they have Sergio Aguero, Maxi Rodriguez, Luis Garcia, Simao Sabrosa, and Jose Manuel Jurado. Each one is a proven goal scoring threat and they have been at one point or the other an integral part of their national team. Out of the five, Los Colchoneros are the most dangerous.
Celtic FC: Undermined by the departure of their best player, Shunsuke Nakamura to Espanyol. Celtic will be looking to Shaun Maloney, Aidean McGeady, and Scott Brown to provide some answers. They have never met Arsenal in European competition but as per CL lineage, they enjoy more success having won in 1967 and entering the finals in 1970. Those were the days of Jock Stein, Tommy Gemmell, and the Lisbon Lions. Celtic get to the CL beating Dinamo Moscow, 2-1 on aggregate in the qualifying rounds.
RSC Anderlecht: The most successful Belgian club. Anderlecht was in the news recently when their defender Jelle Van Damme was sued on racism charges by Oguchi Onyewu while the US defender was at Standard Leige. The club debuted Nii Lamptey, an enormously talented player instrumental to the success of the Ghana youth squads of the 1990s whose story of too much too soon has become a tragic byword in international football. Anderlecht won against Sivasspor, 6-3 on aggregate in the qualifying rounds.
FC Timisoara: The Romanian club has never won the Romanian league with second place as their best finish last season. They are in an ownership dispute right now. They booked their place in the draw with two draws against Shakhtar Donetsk, progressing on away goals.
The answer is pretty self evident. No Fiorentina and Atletico.