XRPs have done something similar in the recent past. XRP was once at 10,000 XRPs per 1 btc and then dropped to 140,000 XRPs per 1 btc. Now, it breached the resistance at 10,000 XRPs and no one knows how high it can go. It has been at about 7000-8000 XRPs per 1 btc for a surprising time, this suggest it can still go up some more. But once it starts dropping, it will drop back to 20,000 XRPs very fast. And probably won't stop there. At 7000 per btc the 100 billion XRPs have a value of 14,285,714 btcs. That is more than the current number of bitcoins. Therefore, the Ripple system now has more value than all Bitcoins together. True, many of the XRPs are in the deep pockets of the developers of Ripple (they told they will give away half of them, but what I see is they reducing the amount of the give away several times) and not in circulation, but they exist and must be taken in account. This suggest that XRPs are in a big bubble that will burst like all of them do.
I agree with the caveat being that all that opencoin needs to do is sign a few partnerships to use the network for int'l remittances. Or if they could do a deal like what bitinstant has with walmart and 711 then I think we would see the value increase again.
Given that their growth is more "managed" growth, being an actual company, it is entirely possible that XRP could break parity with BTC which I think is something like 1 btc to 1189 XRP. Again this is assuming that they manage their business development and partnerships fruitfully.