Looks like the user interface and the font rendering have both been tweaked. Google indicates it has more work to do over the next few weeks, and I'm curious to see how long other browsers and applications take to follow suit. The MacBook Pro isn't the only system with a high-density display, of course. Asus' new 11.6" and 13.3" Zenbooks feature 1080p displays. Those screens may have fewer pixels per inch than the MacBook, but they're huge improvements over the 1366x768 resolution all too common in modern notebooks.
Source: The Tech Report