NO. Play the video game on Sony Playstation 2 (or watch it played on YouTube), "Disaster Report" or "Raw Danger," to see the folly of living on a floating city. However,
YES. "Seasteading," or the forming of "micronations," might provide an option for some, to escape stupid and corrupt governments, and that might be a reason that might make floating cities a viable option for some.
But there is plenty of land for naturally-expanding human populations to spread into, so floating cities do not appear to be an economical way to accommodate the continued natural increase of humans.
Yes. The oceans of the world will eventually create a viable solution for rising property costs and limited land space for a growing world population. A form of the technology already exists and is being employed in the United Arab Emirates. They were able to create an island and build large structures on it. It is only a matter of time before we are able to create a mobile floating city.
I guess this depends on how you define "near," but we definitely don't have the technology any time soon (next 5 or 10 years or so) to have this happen. Even if we did, I think floating cities would destroy the cities still on the ground. They would block sunlight and create pollution. I'm not so sure floating cities are the answer.