Yeah maybe 100 posts could be considered hot or something.
That would be completely pointless and misleading. All continuous threads like e.g. Mass Effect thread would then 50% of the time be "normal" topics and 50% of the time they would be marked as a hot topic.
The problem is that the way a hot topic is defined on this forum is plainly and simply wrong. A topic is not hot when it reaches a certain number of replies. If a topic were considered hot when it reached 100 replies then even if it reached that number of replies by having a single reply each day it would be hot - which makes absolutely no sense. A topic is hot when it maintains gaining a certain number of posts per minute for some time. For example, for this forum it would make sense to consider a topic hot after it maintains gaining at least 0.5 posts per minute for at least half an hour. After that, if the number of posts per minute drops below 0.5 posts per minute for longer than ten minutes, the topic loses the hot status. That's approximately how hot topic recognition operates on some other forums, at least.