The chaps over at motherboards.org bring you the installation and comparison of Windows 7 and how fast it boots in comparison to Windows Vista:
In related news, HCW spent several weeks testing both Windows 7 and Vista on three different PCs, and came to a final, quantifiable conclusion:
If you have a relatively new CPU, capable of running 2 threads or more, then it is absolutely worth upgrading to Windows 7. In addition to all the basic improvements Microsoft has made, you will be able to get the absolute most out of your PC with Windows 7.
If you are on an old single-core system, and the UI and other new features don't look attractive to you, then there is not much else to get excited about. Most of Win7's performance improvements clearly come from improved multithreaded/multitasking performance, and your CPU won't be able to make use of all that. However, it is still the better option for Netbooks, because of the significantly improved user interface and other improvements. If you bought a Netbook with XP when it was the popular thing to do, by all means it's time to upgrade!
It's good to know that the performance improvements that Microsoft have been talking about all along are real, and totally quantifiable. If you are a student, it would be foolish not to make use of Microsoft's $30 upgrade offer (Canadians get it for $40). And if you're not, it is still worth picking up, to get the absolute most out of your PC.