Rooting is similar to jailbreaking it, as far as I know. Similar to on linux when you have root access, this gives you root access to the phones file system so you can modify it or put anything you want on it.
Heres what I did.
http://theunlockr.com/2010/09/20/how-to ... ed-method/
The only difference, and a major difference, is that my HTC Desire was a new PVT4 handset, meaning Google have patched up all the vulnerabilities.....mostly.
Instead of just running unrevoked3 with the default settings, before I plugged in the USB cable, I opened unrevoled with admin access in windows 7, clicked "File" and "Custom Recovery". I then selected this:http://dl.dropbox.com/u/4481275/recovery-RA-desire-v2.0.1.img
So, in summary, download USB phone drivers, make sure your USB is in Debugging mode, and charge only. Then download Recovery-RA-Desire-v2.0.1.img
Open unrevoked, click File -> Custom Recovery and select the img.
Plug in the phone, and click OK.
Once it reboots a few times, it will load into recovery mode. Do a backup.
You're now rooted.
I think thats everything. Now I just need to find out what I can do now I have it rooted!!

