For those of you who still don't know about it: Amie Street is basically an online music store targeted at small and independent bands (from what I can tell). The feature that sets it apart from all the other online shops out there is the pricing model: Prices start at free and can climb up to 0.99USD when they get more popular. When you've bought a song you can also give it a recommendation and get some credit back when other people buy the song and it therefor gets more expensive.
The whole celebration thing involves a promo code handed out over at TechCrunch.
Congratulations to the whole Amie Street team. You rock :)