Terry had his arms in the air and leaned towards the ball, he blocked it with the upper part of his arm - penalty in my opinion but i would say that.
Gudjohson was in front of Drogba but to the side of Martyn, i would say that he was interferring in play in that Drogba could have passed to him meaning Nige had to take that into account where he would position himself as Drogba lined up his shot - offside but i would say that.
As for BT's celebration it was quite low key, he was flicking his fingers acting like he might say something like 'wicked' like a hoodie wearing chav in the arnedale centre, it was done in jest and Arteta looked like he enjoyed it.