A bubble in slow motion, someone called the present economic environment. I think it's an apt description. Extreme "quantitative easing" (I refuse to take fed speak seriously) has only taken effect very, very slowly. Why? Because all it really was was recapitalizing banks which had enormous gaping holes on their balance sheets after 2008. They have been able to fill the tanks now, getting money hot off the presses for a song for a decade, and finally it has started to trickle into "the real economy" and actually lead to commercial and industrial growth.
Another dampening factor has been the regulations introduced after 2008 like S̶a̶r̶b̶a̶n̶e̶s̶-̶O̶x̶l̶e̶y̶ Dodd-Frank, the moratorium on IPOs has definitely helped to slow things down.
Now things are moving again, trouble is, history has shown time and time again that monetary policy is a ketchup bottle, once it starts having effect it is already too late to moderate it. That's why we have bubbles - suddenly there is too much money slushing around chasing finite resources, markets become crazy and regulators have to slam the brakes hard (in combination with banks predictably finding ways to overleverage, legally or not). Which leads to my prediction: Markets are still not crazy enough. Crazy, but not enough to look like the part where it all blows up. So I am betting on at least six months more of "growth" (i.e. inflation) before the inevitable crash.