MIT's Technology Review is always interesting. I also like "top-level" academic/professional journals like Communications of the ACM, IEEE Spectrum, Science, a

MIT's Technology Review is always interesting. I also like "top-level" academic/professional journals like Communications of the ACM, IEEE Spectrum, Science, and Nature. There are so many sub-specialties in these fields that authors put in a lot of exposition to keep everyone on the same page. The result is usually surprisingly readable, and there are a lot of implicit pointers to more information if something really catches your eye. They're not cheap, though.