I'm looking forward to the XP3 release almost just to see the effect it has on the other cameras. I think you might be right about the XP2 being forgotten, but at the same time, I suspect a lot of the love and interest in the XP1 comes from those who only came to it later in the product cycle when it became a much more affordable camera, either new or used. I was one of them - I lusted after but hadn't a hope of ever owning it when it was new, but years later paid literally nothing for it as part of a black friday deal a few months before the XP2 came out, and for the past few years now it's been very cheap to buy and try used.
The XP2 hasn't had that moment yet - even now, well into its third year and with the XP3 breathing down its neck, it's still an expensive camera. It hasn't really gotten into the hands of the tinkerers and the hobbyists who might like to try it out as a second or third camera but can't justify the cost. That'll change soon, so it'll be interesting to see whether it does just disappear without a trace or whether a new generation picks it up and runs with it as a budget marvel or new "classic".
Personally I'm all in with the XP2 still. I went through my agonising over the IQ differences but concluded that it really is very subjective and even my opinion varies wildly over which is "best" in different scenarios. What's less subjective is how much more capable and complete an overall camera the XP2 is in many other ways. I've owned it longer than the XP1 now, taken many more pictures, and amongst them many more of my own favourites too.