anyone know why some themes the popup hotlist title has huge text?

depends on the font size the themer sets it as

wow wouldnt u think id check it? its the same font as the rest of the popup.

specify the themes you're having problems with, maybe they use fonts that you dont have installed in your system. usually this fonts come included in the theme, but you need to install them, and most of the times it's specified in an included manual which everybody that installs the theme should read.