I find myself a million times more "productive" in Sublime Text 2 with a "light" theme (Soda Light) than previously when it had a dark theme (the default one). I do look for substance, but we are all machines and can't fight over our limitations. My eye thanks me when it can visually see an "orange" function instead of having to look for a "black" (i.e. misspelled) fuction in code. It's not my fault - eyes appreciate semantically color-coded (or typeface-coded) blocks of code/article/etc (my last sentence is poorly phrased, as a non-English it's hard to articulate what I want to say but I'm sure you understand what I tried to say).