I still love my last theme LUSH (by the way Jerko One has switched to a new design, check it out). I'm still using it at a site I hosted for my Marketing Professor here.
Switching theme once in a while is my way of learning eventually I'll design one for myself but I guess I still won't keep a theme for too long.
Since I moved to WordPress about 8 months ago I saw a trend of theme design getting very complicated due to WordPress Widgets and may be the use of menu driven customization is "fashionable". These are OK for average theme users who want simple and quick customization. I don't like them because codes required by these new features are in my way of manual customization.
E.g. this theme is clean in their theme files, no widgets no menu driven codes so I find it easy to customize. There are only 9 files while LUSH and Kubrick has 14 and 17 files respectively.