I was going to stay out of the MP discussion. But reading through the comments, a few reactions sparked.
I'm principally opposed to the argument of including things in a game in order to reach another audience, or a bigger audience.
That goes for MP as well. However, the case is not clear.
MP definitely saved CoD's bacon when various developers lost their marbles about what was special about CoD. But I also predict it won't work indefinitely.
I'm more doubtful about that ME mp had a positive effect on sales. It definitely has for the longevity of interest in the game. But that's not immediately the same. People actually looking for MP simply look elsewhere than to a RPG for that. It was more a case of ME players discovering that they liked the MP. But I suppose the prolonged life of the game will have positive effects for the sales of a follow up. Otherwise, likely the ME3-end would have been the end, literally.
Including MP in a game will definitely affect SP. But again the case is not clear that it will necessarily be in a negative way. The changes to the structure concept may be positive, i.e. force the developers to do it the right way, which will open up things also for the SP.
I don't believe that the concept of separate budgets actually work. But it is a way to get a higher total budget, and if you're clever about how you go about things, it might mean spilling over into enhancements also to the SP.
Basically, it's not clear that including MP will be either positive or negative. But it does provide the publishers with a sort of additional safeguard, like the examples of CoD and ME indicates.
If DA:I includes MP, I suggest we don't automatically assume it's all for bad, even if we don't want MP, or don't like MP. OK, let's see what's it's about, seem a more reasonable reaction.
And this post does not indicate that I think the 'big announcement' will be about MP. It could be anything.