LOL very original answer
Seriously, it's impossible to predict future of bitcoin.
For example, in the past hotmail email and msn search was the most popular on line and we was thinking that this will never change.
Now, we see that gmail and google search are the most popular online.
So, right now bitcoin is the most popular virtual currency but if someone start another virtual currency with better potential, people will naturally accept new ''great'' thing and forget bitcoin.
Let's wait and see what happens.