Lets sum up everything first. Well first, Ash Greninja is now a Mega Evolution. Next week is a fight with Team Flare and Zygarde 50%. An online Pokemon store in Japan reopens with several new merchandise campaigns.
Pokemon GO is gonna be shown off at a conference next month. GO is said to have connectivity to the next main games. So they might have to reveal whatever before showing off GO.
I wouldn't look at CoroCoro when it leaks around the 11th-12th. I would be looking for a global announcement method between this Tues and Wed. Global announcements can't be in CoroCoro because it always leaks early. So I wouldn't place my money there. Either by web only or a direct.
Nintendo almost always has a direct in February. 2015 didn't but it did have one in January.
Take a peek for yourself...
https://en.wikipedia.org/wiki/List_of_Nintendo_Direct_presentations
Fire Emblem and Zelda have stuff coming real soon. Keep an eye for a direct. BTW there hasn't been a direct for three months!
Next are some past CoroCoros from B2W2. Note it was announced on Feb 22 after CoroCoro.
January 15: CoroCoro has promised that, within their next issue due out on February 15th, it will provide more world's first information, but this time in regards to the new movie. Elsewhere in the magazine, it promises a scoop about the main Pokémon of the movie next month indicating that a new Pokémon is to be revealed, presumably the legendary Pokémon; Keldeo. We'll provide more of this as and when it comes
February 15: The final image of CoroCoro has been released. This image, as usual, provides a teaser into what will be contained in next month's issue. This teaser states that in the next issue, due for release on March 15th, there is to be another bit of surprise information. This information is said to not just be about Keldeo, with it stating it will post "more than the report of Keldeo". It is likely that the distribution details of Keldeo will be given in the issue, but it is unknown what else they will reveal. We'll provide more information as and when it comes.
B2W2 announced on TV on Feb 22nd.
March 15: More info on B2W2.