Immortality would introduce some new challenges (possible cultural stagnation, an even more entrenched elite class (only a problem if you're not a member of the

Immortality would introduce some new challenges (possible cultural stagnation, an even more entrenched elite class (only a problem if you're not a member of the elite class I suppose), etc.), however, it would also solve (or at least mitigate) a lot of problems, some of which are hinted at in the article (medical costs, social security, etc.) I'm not sure overpopulation would be such a huge problem - birth rates are already declining all over the world and I suspect indefinite lifespans would only accelerate that trend. Besides, there are still plenty of ways to die other than old age, we wouldn't be truly 'immortal' :)