Agreed, I am seeing similar thing on other sites - for an extreme example, MMORPG.com has only 8 (!!) "hot" spots.
I've even made couple experiments and each confirmed that, like, 99% users never go beyond that: a random post will get, say, 120 views during 10 minutes in the "hot" window, and once it sinks out of the window - 3-5 views will be added over the whole next day.