As for how it was, that depends 100% on how much of the game you play and how deeply. If you're into the BGS, it's been a shocker. If you like to just casually pootle around the galaxy doing this and that, you'll probably only notice the common disconnects and freezes, and otherwise enjoy the plethora of new features.
The major issues right now are G5 material gathering is now completely random, and the BGS has a lot of apparent bugs (things not working as they once did, or perhaps should). Apart from the reular disconnects and freezing, which I'm sure will be resolved soon.