Hey Ken,
That is the current behavior and the old one was more or less wrong.
When the map loads for the first time it can be centered on the hotspots you have, but when you zoom into an area and change to a different category, then you don't expect to be zoomed out and placed over the north pole, because there is 1 hotspot in this area.
We've improved the behavior when you search and now auto zoom out only when there are no hotspots in your current area. And we'll do this with the category change in the next release. Up until then you'll have to live with it, till the new year comes
Cheers,
Daniel