1) although you can hope for it, you can't guarantee something will become viral. threewords.me could have just as easily been another "project" had it been pushed out at the wrong time, sent to the wrong people, etc. etc. there's a lot of luck involved. i'm glad it took off the way it did. Mark made sure he would maximize the viral potential by having it easily shareable, etc, but that alone didn't make it viral.

2) i'm just jealous that he got real time experience in learning to scale his servers to support the crazy growth in users. not many people in the world have experienced viral growth with their webapps or startups. so congrats to Mark.