The spoiler list is here, for reference or if you haven't seen it yet.
My first thought...is actually that it feels really early for the spoiler to be out! The set isn't out until Jan 27th, which means the pre-release is a solid 14 days away (as of this writing). That's a long, long time for people to take a crack at testing this set. WotC doesn't usually show the goods off this soon, right?
That suggests to me one of two things:
First; they had it on pretty good authority that the set was going to be leaked. And if that's the case then they might as well get ahead of it, ruin the credibility of any leaker and show off what they have on their terms. It's a good PR move, if that's the case.
Second: the displeasure players have expressed with the current Standard format has put a bug in WotC's ear and they want to show players that there are some powerful, interesting tools to shake up that format and keep people interested and invested in playing. That's still a good move but it's definitely worrisome, that Kaladesh-intially wildly hailed as a very interesting format-has fallen into the patterns of...well, Mirrodin, actually.
Historical note: every time WotC decides to get cute with Artifacts, something like this happens. See also: Mirrodin and Urza's blocks. Mirrodin especially had so much untapped potential-and none of it mattered because of affinity. Kaladesh is a little different, as the oppression is also coming from Emrakul but how is Emrakul arriving so quickly? Aetherworks Marvel.
I rest my case.
Or, I did before Monday's Banned and Restricted announcement.
They say that they wanted to allow players to test an environment that would actually exist; meaning, since they knew that the B&R announcement was coming, they wanted to give players as long as reasonably possible to test for a format that was coming, not the one everyone expected.
This is another good PR move, it just arrived in a way I had not seen coming.
Interesting--but that's a lot of non-review stuff for one day, so I'll get to an actual overview on Thursday.