First up of course is HSJ. It looks like it will come with a lot to make fans happy as not only will there be the actual wall calendar but it will come with stickers and a 144 page dairy.
Kis-My-Ft2 will have a weekly desktop calendar that will come with message cards according to the CDJapan listing. They happen to be the only ones with any kind of description of what to expect for their calendar at this point.
Next is Sexy Zone. What is worrisome about this calendar is that there is an image floating around for all the calendars and for the group only the older three are featured.
Sexy Zone Calendar 2015.4 - 2016.3 Johnny's Official Calendar (Title subject to change) [2015 Calendar] / Sexy Zone
Johnny's Juniors do not really have anything up to say what exactly their calendar will be. It will either be some kind of book or come with one as there are plenty of Juniors to feature in it as it is every year.
While I passed on getting a calendar last year I think I may see about getting one this time around. Especially since my love for Kisumai has resurged so I would like to have one of theirs. With their ages they may not have long getting these kinds of releases as these do tend to go to the groups with younger members. Which makes sense as these are school calendars.
In any case I always like seeing what the calendars are like as some end up being really nice or creative.