I'm betting on both! They are two completely different systems with different use-cases. The cryptocurrency pie is incredibly large and Ripple does not detract from Bitcoin nor vice versa. In fact, Ripple makes the pie larger!

Even though I can't stand the alt-coins, it is interesting that Ripple will also benefit the alt-coins since it will make them more liquid. You'll be able to spend your litecoins at any merchant that currently accepts bitcoin, when bitcoin "bridges" appear on the Ripple network.

What I keep saying, which unfortunately gets drowned out in the chorus of "scam, bla bla" is that Bitcoin users already have to extend trust! Except for the very few who don't use an exchange... See: