I'm the one who enabled the migration targets earlier today. I was going to post an announcement here on meta, but some other stuff popped up so I punted it until tomorrow... well, I guess I don't really need to anymore?
It was pointed out to me at the end of last week that CR was still missing migration targets and community ads*, which should have been enabled with the first part of graduation. In my haste to fix the problem, I just enabled a couple targets and let the mods know. I picked based on stats of where CR has actually frequently migrated questions to in practice and the fact that this community has an excellent track record of migrating questions appropriately (by which I mean that migrations are not rejected on their destination sites).
I apologize if it feels like I was stepping on toes or pushing things out by diktat here, and it is entirely possible that I was too hasty in choosing targets, too. I was intending to give y'all something you deserved and we dropped the ball on, and that I was under the impression you wanted. I don't think we have any formal community consultation process for choosing migration targets, but feedback is always welcome here on meta... if you want to discuss the pros and cons of specific migration targets though, please start a new question, so that we're not mixing up two issues in one place ("how the current situation came to exist" vs. "are migration paths desirable and if so which").
* As for community ads, those run on half-year cycles, roughly aligning with the first and second halves of the calendar year. I'm sorry that we didn't get ads up and running for you during the current cycle, but they'll definitely be working starting with the next cycle (so, Jan. 1, 2016, give or take a few days).