And once again nobody is talking about TH, or Loki for that matter - he has 2 options left in his contract to be used at Marvel's convenience, maybe a small cameo here and one in the Infinity Wars, or both in the Infinity Wars, or nothing at all.

http://www.etonline.com/news/179620_cate_blanchett_joining_thor_3_mark_ruffalo_confirms/