ok, time for some scenario's and guessing
Let me say at the beginning that this is pure speculation, and I assume XMR manages to somehow establish itself as the best anoncoin before one of these scenario's start. The scenario's I can see taking placing from april/may 2016 onwards.***
SCENARIO 1: Mega BTC bubble:
If the influx of new users is very very large, a lot of altcoins will be overlooked. Chances are that XMR will be overlooked also.
In this case, XMR may go down in BTC terms, but I expect it to go up in USD terms. BTC will be established as "the one and only cryptocurrency" and XMR will be in the shadows, a bit like tor (or I2P) versus regular internet users.
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SCENARIO 2: Small BTC bubble:
If the number of new users is not that big, and we see a bubble to maybe 2000 USD, then at first XMR will go down in BTC terms, but I expect that a significant number of "old time bitcoiners" who have a nice stash want to diversify. They don't necessarily want to cash out all in fiat or precious metals, so some of them will allocate a part of their BTC to buy the promising alts, so at the end of the BTC rally, XMR could follow the old LTC pattern and do a moonshot in BTC terms.
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SCENARIO 3: consolidation of BTC (+ small hype due to block halving or a little decline)
Actually, I think this one is the most likely. Why I don't see a BTC bubble in 2016? 2013 was crazy and the market needs time to digest this. Also, everybody seems to expect a bubble due to block halving. But I think a lot of people are buying their coins in advance now, so I think the whole block halving will be a disappointing event. Also, "halving of emission" is nothing to be proud of or like: the more halving happen before cryptocurrency reaches mass adoption, the harder it will become to reach that mass adoption. People will start to realize this.
Also, BTC is pretty much known by the tech community. They maybe don't know the details, but they know. If they were interested, they would join us no matter the price. So the next step is a difficult one: bringing in regular people (who aren't nerds, anarchists or coders). This isn't something that can happen overnight. We will need to see a lot more companies doing something with BTC, we will need to see it becoming more user friendly, etc. This won't be a big bubble at the start. It will be a slow process. This is how I potentially see BTC doing in the next 12-18 months:
This would also be a perfect scenario for XMR to grow, both in BTC and USD terms. people will slowly start to hedge against BTC by buying XMR. This won't be a big bubble, probably a rather slow rise of XMR in BTC terms.
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BONUS: my "fair value" calculation for XMR:
I know this is BS, but it's fun to do BTC was very small and almost only used at dark markets and as "the ideal cryptocurreny for anarchists" in 2012. it had a value around 5-10 USD. This seems like a fair valuation if XMR manages to attract that community.
Looking to coinmarketcap, we see LTC with a market cap of 135 million USD. And this is declining. It has been bigger in the past. LTC is only surviving due to the large liquidity. this liquidity is used for mixing coins. This can change fast: if people start to acknowledge the value of XMR (the anarchists and dark markets), XMR could get a lot of liquidity while LTC is in a downwards spiral. If we manage to become the dominant "altcoin" which certainly has more features than LTC, a market cap of 250 million USD doesn't seem to outlandish. With 10 million coins, this would mean 25 USD per XMR.
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Am I too bullish? Am I talking bullshit perhaps? Let me know