[huntse]

Well to answer your final point, there is never any absolute guarantee, but your best insurance against unemployment is to become really good at what you do. The second best is to make what you do be something commercially valuable. If you combine these two it's very unlikely you'll ever be unemployed for long.

Now to the first point. The most important part of learning is the process itself: ie learning the thing itself is less important than becoming good at learning. Once you have a sound grasp of the basics, the more diverse your curiosity and the deeper the insight you are able to gain into each specific technology, the easier it will be for you to pick up new ones. There's no excuse for ever becoming obsolete. Read widely, maintain your curiosity and keep learning.

Finally, the technologies you have picked may or may not be the way of the future. The future has a way of being unpredictable. Don't be so sure that you know what is going to happen that you close your eyes to what is actually happening.