I suppose that the "magic algorithm" behind What's Hot really requires more FPs spent than what is available in many of the states in the US. However, I also understand that the current results based on where you live are not very useful, as for many areas the next cache on the map is many hundred miles away. And keeping in mind that the US states are comparable size as the countries in Europe which each have their own map it sounds reasonable to follow the suggestion of geoGRAV.
A workaround may be to just return 2 or 3 times as many results for the US than for smaller countries (currently it seems the number of results is the same for each country). Or even better, return a certain fraction of the total active caches in that country, this would scale with the activity in the area.
