Wow, this is a very interesting question.
Infact, it is agreed upon by the scientific community that evolution does happen quickly in small groups of people, when the pressure to change is high.
That is probably how the human species evolved from another primate in a small area in Central Africa around 200,000 years ago.
Infact, most species probably undergo times of large changes, and then times of relative stability in gene structure.
As of yet, we dont know of any significant threat to human existence, by such risks strike quickly and often without warning. In that case, humans would be forced to evolve or dissappear.
Small incremental changes also seem to be happening, in human society, but not fast enough because it doesn't seem to be a life-death matter.
Another possibility is that we will get to know our gene structures and how to manipulate them. Through this mechanism we will "evolve" , though this may itself pose risks to the stability of society. People would have to set quotas for increasing-- say intelligence -- in one generation, strict rules, and constant monitoring to see that the system of man-made mutations becomes successful.
This would mean that skies are the limit for us, as we can make these mutations and test them at a much faster rate, maybe even through computer simulations( and eliminate the ethical aspect of it). These computer simulations may themselves become people, and we will be like god. But thats not the point. Thats a completely different topic.
But yes, evolution as we know it is over, or will take too long for us to observe (in case there is any unforseen disaster forcing us to change)
