It looks like a small update has been pushed out across the Miiverse today, according to an official post on the Miiverse itself. "By popular demand," the limit for the amount of characters in each post has been increased to 200 from the previous limit of 100. Additionally, filters have also been enhanced, including the ability to search for older popular Miiverse posts (rather than the limitation of newer posts prior to the update).
Honestly, Nintendo doesn't have to do a whole lot to make the Miiverse better. It's one of the most enjoyable social networks I've ever been on, and I barely even post. Just going on and checking out passionate community pictures and messages is good enough for me some days.
Miiverse Announcements [Miiverse]