Amp'd numbers

Back in Sept of 06, Amp'd announced that they would increase the subscriber number by 50K to 100K. At the end of 06, they made the number. Q4 saw an increase 70K increase. How did they do that?!

Not only that they claimed the ARPU was $100/month. 30% of that is from media download. I started wondering if any financial models were used to achieved this type of number.