Many months ago I read a book called This Crowded Earth by Robert Bloch. You might be able to download it here. The book was written in the 1950s and tries to make many predictions about what will happen to our world once more and more people start to inhabit it. Some of these predictions are a fun zeerusty experience. But others are frighteningly true. In the book Block sketches two possible futures: a utopian one and a dystopian one, each trying to deal in their own way with the increase in population. I'm sorry to say that our current society is far closer to the dystopian one than it is to the utopian future.
A good way of noticing the overpopulation is by watching movies. There's so many things portrayed in old movies that you just can't do any more in the present day. It will show you a famous landmark and miraculously there's hardly any people there. Movies made this century often set their timeframe a couple of decades in the past just so they can circumvent pesky little problems like modern-day security regulations, crowds around busy areas, presence of mobile phones etc. Not all of these discrepancies between movies and real life are in favor of the movie world (many a horror movie would've been lame if the characters had had access to mobile phones), but they do highlight a difference between the 'idealized world' and reality.
Somehow I never noticed how overpopulated this world was while I was living in Japan. You might find this strange, considering that I was living near Tokyo, one of the largest population hotspots on the planet. But Tokyo manages quite well, comparatively. Their public transport is super-efficient, as is their building style with lots of tall buildings and small apartments (much like the dystopian future presented in the book). But Japanese people are homogeneous and easy to orchestrate, quite unlike the madness and hatred that is the consequence of the melting pot of cultures in London and New York.
It was only after moving to London, being stuck in a busy commute almost every day, that I realized how serious of an issue this is. This is no small problem. The world population is increasing like crazy, and I think countries are severely underestimating how serious this problem will become. Or perhaps they are not underestimating it, but they simply don't know how to deal with it. Each country adopts their own policies regarding rental housing in crowded areas, health care, how to treat elderly people and so on. Not every country's solution will scale. Perhaps none of our current solutions will.
Personally, I've given up hope. I've seen the situation as it is in present-day London and New York, and I despise them both. I cannot imagine that either of these cities will be a pleasant place to live in at any point in the future. To me, the only hope I see is to move away from big cities and overpopulated countries. I'm sure we'll see a lot of that over the course of this century as people's riches increase and technology allows them to be connected or even do their job remotely.
Small islands are a great way to escape. My personal goal for this year is to find out if I can live on the Seychelles and still earn money. Failing that, some other island might be nice. An interesting option in the long term is Japan. It's one of the most connected countries on the planet, and you can find high-speed internet virtually anywhere in the countryside. Their strict immigration policy combined with the lack of childbirths means that the population count in Japan is expected to decrease a lot the coming decades. This will probably have consequences on Japan's immigration policy, but even if it doesn't, Japan is a place to consider.
The place I least want to be in is West/North Europe. All the developed countries there have a rich history, meaning their cities' infrastructure is utter shit. There is no way they'll be able to cope with the population increase. The best Europe can hope for is that the surrounding countries rapidly increase their quality of life so that they can become a viable alternative to people that are thinking about emigrating to Europe. Since I'm making future predictions here, try this one: Russia might turn out to be a very nice place to live, given a couple of decades to get their act together. China and India are without hope. Their capital cities are ruined beyond repair and will never be a nice place to live.
Seychelles. Japan. I wonder what North Korea will look like after two decades of Kim Jung Un at the wheel. If all else fails, we can always go to Mars.