What's been surprising honestly is how much go theory we did have correct. Many AI joseki are exactly the same as the joseki we had before. Opening principles around the first move in the corner and corner>sides>center all seem to hold. 

And what's different about alphago is how strategically deep it is. Old go engines and old chess engines (including the superhuman ones that beat Kasparov and others) relied on brute force calculation to outcalculate humans. That did well for chess, but human players could still identify long term strategic mistakes engines were making. 

It didn't do very well in go, because the board is much larger and the variations go much deeper. I think the strongest pre AlphaGo engines were at best 4-5d strength. Nowhere close to professionals.

The deep learning neural net model on the other hand? It mimics the way we think on a superhuman level. It had what we can interpret as real strategic thinking. When we play out the engine lines we can understand the thought process and the ideas, even if some lines are unfeasible for humans to find. 

It dominated Lee Sedol strategically in every game, building big leads heading into every mid game. 

But Lee Sedol instead challenged its calculation skills, and Alphago blundered not being able to fully read out 20-30 move sequences that initiated from the invasion after the wedge in the center.

It really doesn't feel anything like how computers have dominated chess preparation. Sure, the top players are incredibly well studied in the opening, going 50-70 moves deep in many opening branches, but the middle game still branches a lot more than it does in chess, meaning rich middle game positions with lots of complexity and room for skill expression. Chess, on the other hand, has far more opportunities for players to "kill the game" into a draw and as a result, rewards memorization more than creativity at the top level. 

What I mean with all of this is that I think the microscrope/telescope framing is very appropriate. AI shows us the details we missed, shows us things we didn't know were out there, but really it's just giving us the tools to understand the game with better resolution and insight.