Yes, when you trade BTC/XRP on Justcoin, you're using our order book which is made up of offers created by our customers. When you use the Ripple exchange, you're dealing only with the Ripple network.
I think my question was ill-phrased. For any currency conversion you need an issuer (and only one at a time). If I set Justcoin as issuer, then the same orderbook appears on ripple.com/client as on Justcoin:
so, trading with this orderbook either on ripple.com/client or justcoin.com is the same thing, correct?
Also, is NOK.XRP coming to Justcoin?
Not at this time. If we create every pairing of currencies, it would fill up your screen. That's why we always use BTC as the base pair (BTC/NOK, BTC/EUR, BTC/LTC, BTC/XRP)
I agree pairing
every currency makes no sense. Justcoin is, however, the only exchange to offer entry to BTC from NOK, so NOK.XRP just makes sense as anyone entering from NOK otherwise have to convert to BTC and then to XRP.
In any case, suppose you were to support NOK.XRP, then could you answer this theoretical query:
Would supporting NOK.XRP mean you'd have to issue NOK IOUs which I could then theoretically trade for another currency (fiat or crypto) with a second exchange? (not that anyone else does so now, but that might change in the future)
To do so, I would have to extend a trust level with Justcoin up to the amount of NOK I wanted to trade. Also, I would have to extend trust for the EUR I'm buying from the other exchange. Suppose I then redeem my EUR for cash. Did the other exchange now just inherit my (theoretical) Justcoin NOK IOUs?
and this is where the migraine starts...