No, I am not encouraging you to jailbreak your phone. If you are happy with iPhone OS 3.0, stop reading this mail. If you unhappy and wanted more, read on. The Dev-Team has done it again, jailbreaking their favorite phone.
The instruction seems easy. Not so sure about the outcome. I read some comments from their blog post saying that after install, it has some issue.
Remember, don’t do it if you are fine with your phone now and don’t do it if you are worried about your warranty (although I believe a hard reset will change back everything).