Your comment about Biebercoin indicates that you don't (want to) really understand why Bitcoin is not Linden $s, or WoW gold, or Faceboot credits, or Canada's MintChip, or whatever.
Bitcoin is not any of those because it is decentralized. Successfully decentralized. And it has grown through a vulnerable phase that no other decentralized digital currency has made it through. Bitcoin made it through because it was not a threat to any other digital currency, and not seen as a legitimate threat to any other currency, fiat or otherwise. In other words, it was not attacked back when it was vulnerable. A digital currency, decentralized like Bitcoin, hoping to be the successor will be a threat to bitcoin. If it relies on proof-of-work just like bitcoin, it will need some very deep pockets to even try making it through the vulnerable phase.