I try to keep the lines short. In this case, I would break before the assignment and after each parameter. I also put the comma at the beginning of the line to make it easy to add new arguments:
int SomeReturnValue
= SomeMethodWithLotsOfArguments(
Argument1
, Argument2
, Argument3
, Argument4
);
Using this kind of layout is a lot of work in Visual Studio, but Emacs makes it automatic for me.