Unfortunately I believe there is a 0% chance it will be even close to 1 million. This is solely based on where we would be as a society. If bitcoin was in that sort of demand, other cryptos would fill that roll (e.g. Litecoin, XEM, etc). I'm invested in bitcoin, and use it other than for pure investing. Based on this, I believe it has plenty of room to grow.
Honestly, I cant see it above $10k, and I dont think that will be anytime soon at all.
I'm with you on the altcoins/other cryptos picking up the slack.
If we see a hyper-inflationary period in the US economy, though, it's possible that $10,000 might be in the rearview. (Of course, bread would be $27.50 a loaf.)