One of the more touted features of the upcoming New Xbox Experience is the ability to install games onto your hard drive (watch how to do it). In an effort to quantify the benefit, MTV Multiplayer's Stephen Totilo has created three videos comparing the load times of running DVD vs. hard drive using Grand Theft Auto IV, Fable 2 and Gears of War 2. The difference is between 9 to 15 seconds for the first load, and presumably more "now loading" seconds scraped off other sections of each game.
While the verdict is out on whether or not it's worth your time to install (judging by Totilo's install times and our own, it seems to be a steady 1.7GB per minute), it's worth noting that, with installation, the console is noticeably quieter and is less likely to give you the feeling that it's about to explode.