The folks at Capcom have made a lot of murmurings about plans in the works to celebrate Mega Man's 25th anniversary. However, that doesn't mean you should go expecting some amazing new game (though a number of fans have regardless). When questioned about what's going on, Capcom's Christian "Sven" Svensson made this response:
[...] In December "some but not all" plans for the coming year of celebrations will be shared. There are many moving parts and not everything will be done and final come December. No one has promised a game or even an announcement of one at that time. Please do keep expectations in check.
And that's all there is to the story, really. I know a lot of people are anxious, but getting wound up and constantly asking questions isn't going to make December arrive any faster. And the truth is that it's unprecedented for a Mega Man title to be created specifically to honor an anniversary, or as compensation. Mega Man may be having it rough these days in the games department, but that doesn't mean Capcom owes us a game in turn, even if some of us would like it to.
Chances are you may not like what Capcom has in store, and I think that's the source of a lot of this anxiety. But if you keep your expectations in check and try not to be so pessimistic, you might find what they have cooking is actually pretty cool. Best advice I can give, anyhow.
Thanks to Joshua for the tip!