It appears that as prices for Ripples rise (they are currently valued higher than Bitcoin's market cap), OpenCoin will reduce the rate of distribution instead of sticking to a plan. Back when they first began handing out in this forum, they sent 50k XRP. They reduced this slowly, and now they are giving out 1k XRP. So, I believe they think that being valued over Bitcoin market cap is a fair price, or that they think they must maintain it to continue generating profits selling their coins.

Because OpenCoin has no plans in monetary policy and likely spontaneously changes their plans based on where the price is and where they would like it to go, it is probably prone to bubbles, even more so than Bitcoin, where the block chain relentlessly distributes according to an algorithm, no matter what.