Here is the instructor Pascal Van Hentenryck answer from the coursera forums:

"Thanks for pointing this out.

First, we obviously cover linear programming and mixed-integer programming in this course. These techniques are indeed very successful in practice and I hope that you will also enjoy these lectures. They make up a third of the class. The references

Integer Programming by Laurence A. Wolsey
Integer and Combinatorial Optimization by Laurence A. Wolsey, George L. Nemhauser
Large Scale Linear and Integer Optimization: A Unified Approach by Richard Kipp Martin
Introduction to Linear Optimization by Dimitris Bertsimas, John N. Tsitsiklis
Understanding and Using Linear Programming by Jiri Matousek, Bernd Gärtner
Theory of Linear and Integer Programming by Alexander Schrijver

are also provided in the additional material. The work mentioned in the introductory lectures include many applications that are based on mixed-integer programming. So I am not sure where this person is coming from with her/his comment.

This being said, constraint programming and local search are also very successful in practice, often for different types of problems. So this class aims at giving an introduction to a subset of the techniques that are successful in practice (there are other too) as an introduction to the field. My research group uses all three of these techniques to solve large-scale problems in logistics and supply-chains, energy, and disaster management. Some of the problems we solve require the three approaches together to achieve high-quality solutions. To paraphrase John von Neumann defending George Dantzig: "If this technique applies to your problem, use it; otherwise do not".

We also cover column generation and large neighborhood search in the advanced topics. I used to cover Lagrangian relaxation in my class at Brown and we may add a lecture on this. This class has almost all the material of my optimization class at Brown University but not all, since it is a shorter. We may still add an advanced lecture on this topic (I have an additional motivation now)

With respect to the job market, I would simply say: Go to the Informs conference and see how many people, both from academia, industry, and government, are recruiting. Companies such Google, IBM, Amazon, ... have outstanding groups in optimization. Follow Mike Trick's blog and tweeter accounts to get a sense of how lively this community is (see the community link on the page). I never had a student not find a job and most of them did not go to academia. One of them actually works for ... Fedex. My sense is that the opportunities for optimization keep growing and it is an exciting time for optimization. There are many startups, established companies, large multi-national organizations all doing optimization. Some focus on solvers, some on vertical products, some on dedicated applications, and some of several or all of these aspects. The field has progressed significantly.

There is a lot of work, and a lot of progress, in making optimization more reusable and the tools/solvers are now much better in being more generic. Unless P=NP, this will always be a challenge but there are more generic tools to solve classes of applications. There are also solvers that provide a lot more flexibility to build dedicated algorithms much more simply. Many people (including me) spent their research and academic careers trying to design such tools and some make a significant difference in practice.

Finally, optimization is a multi-disciplinary field. My group employs mathematicians, physicists, engineers, and computer scientists. What I personally find incredibly stimulating in this area right now, is that sometimes you need a physicist, a mathematician, and a computer scientist together to solve a complex problem. We all look at a problem from different angles and there is tremendous values in that. I am part of the INFORMS, artificial intelligence, and computer science communities, and some of the scientific contributions I am most proud of are typically those when I was able to bridge two fields. Many of the techniques in optimization come from a variety of fields and this is also what makes it exciting.

And, yes, I am exciting about the future of optimization,

I hope it helps."