Would it be okay if I made five different Minecraft threads each based on one thing I wanted to talk about?
Actually yes, depending on the circumstances. Forums are meant as a way of categorizing on a high level, threads are meant to be used for categorizing at a low level. You would not want to talk about Bukkit, Canary, or known griefers in a thread where everyone else is talking about the latest client update.
It bugs the hell out of the people who don't want to hear about it, and it bugs the hell out of the people who
do want to hear about it when they have to wade through posts unrelated to Bukkit/Canary/whatever.
Don't like Minecraft?
Don't click on threads with Minecraft in the topic.
A lot of minecraft threads turning up all over the place?
Make a Minecraft subforum.
Replace Minecraft with Ponies for the exact same argument.
So now the question I really have to ask is this:
All of you who hate MLP,
why are you clicking on threads which are quite clearly going to be MLP related?