Just seen this on the Grauniad CL draw page. All the groups ranked by the combined Uefa coefficient of the teams involved..
Group H: Real Madrid, Borussia Dortmund, Tottenham, Apoel Nicosia 405.3
Group D: Juventus, Barcelona, Olympiakos, Sporting Clube de Portugal 394.111
Group B: Bayern Munich, Paris St-Germain, Anderlecht, Celtic 382.857
Group A: Benfica, Manchester United, Basel, CSKA Moscow 321.069
Group C: Chelsea, Atlético Madrid, Roma, Qarabag 320.907
Group F: Shakhtar Donetsk, Manchester City, Napoli, Feyenoord 299.596
Group G: Monaco, Porto, Beşiktaş, Leipzig 222.938
Group E: Spartak Moscow, Sevilla, Liverpool, Maribor 208.922