Five years ago I retired from a position as an enterprise IT generalist. What is the biggest change I should anticipate in networking when I start my new job in about six weeks?

I'll be going back to work after taking several years off, playing with the idea of retirement. I'll be a "pinch hitter" deploying equipment and providing support. I don't know much about the infrastructure.

Is anything going to be wildly different? Is IP6 making a huge difference day to day? Any equipment manufacturers in common use now that were barely on the horizon five years back? Have there been innovations in layers 1-3?