I'm going to take a guess at between 2000 - 5000 USD, I think predictions of 100,000 USD are a bit ridiculous but so are predictions of the price being similar to what it is now or lower.

By 2020 we will have gone through another 2 block reward halvings (one in summer 2016 & one in 2020). This naturally should make the price rise. When you add in increased adoption, Gemini Exchange, ETF approval plus many other things I think my prediction of 2000 - 5000 USD is a pretty good estimate.