User blog comment:Legionaire22/A question/@comment-5337704-20120811195938

Citidel/Avina have a very facist feel in ME2, aliens seem to really despise/distrust humans ME3, the council is back to being multi-aliens, Salarian counciler rescue, is not the same counciler obviousley (less war assest) if saved. Destiny Assencion is destroyed (obviously no war assets for it) Human fleet isnt lowered to 2/3 strength, gain a couple war assets for them.

Im sure there are others, but thats about the extent of the effects from what I remember.