As you may know recent Swell conference organized by Ripple company led to a high degree of speculation about XRP future. In my opinion there is one argument why XRP eventually will fail: governments will issues their own fiat cryptocurrencies. If this happens (and I'm sure it will) banks can move fiat money without going into trouble with any XRP or Ripple intermediation. Of course, it will take time to create and successfully use centralized, closed and regulated blockchains but it is much better for banks and governments to keep their control over issuance and administration of fiat currencies. Now, just on blockchain.