I have to admit, I havent used Visual Studio 2010 much, and only recently have I made an effort to switch to it as my daily editor. One thing Ive noticed is the font rendering in Visual Studio 2010 is a bit bolder than in 2008.

Here we have Visual Studio 2008 on the left and Visual Studio 2010 RC on the right. Both using similar font settings (Monaco 10pt)

Its easy to see how the fonts in 2010 (on the right) look bolder and a bit blurry. From what Ive read, WPF has had problem with Clear Type font rendering. This is the first WPF application I use with any appreciation. 

Windows 7 has a tool to help you tune your Clear Type settings. Just type clear type into the start search bar, and you should find the tool. It only takes a few moments, and the outcome was pretty surprising. Ive very happy with the results after the calibration.