The price of a stock reflects a few things, but one thing it rarely ever represents is the actual value of the company. When a stock fluctuates dramatically, either rising or falling, it signals a shift in peoples' expectations.

Right now expectations are very low. If you were to invest now, and 2.0 turned out to be a hit, the actual value of the company will rise, but the stocks might not rise in proportion. You should only invest in a company as a long term commitment. Forget 2.0 for a moment, and unless you can justify investing in Square Enix for some other reason... I'd suggest not doing so.