Suddenly, my fonts got REALLY thin and I couldn’t figure out why. I started to wonder if it was ever any different or if I was imagining things.
That said, the fonts looked really thin and so did all others.
I’m glad I found this post: http://hints.macworld.com/article.php?story=20090828224632809
that details how OSX can sometimes detect your external display as a CRT and disables font smoothing.
Type this in the terminal to force the mac to always use 2: LCD font smoothing.
defaults -currentHost write -globalDomain AppleFontSmoothing -int 2
The number 2 here corresponds to Medium - Best for Flat Panel. You may also use 1 for light smoothing, and 3 for strong smoothing, as per the original OS X font smoothing options.