As I recall notifications got turned off for the moment because people were receiving several hundred of them when something happened, I believe they're working on getting it fixed so they can turn it back on. That is the kind of the that really needs to be there. I came back in game one day to find every colony I had in an entire section of the galaxy captured by one player cause I didn't know I was being attacked in the first place. Turned out okay since I had just started building my fleet like the day before, so I took them all back, along with all the ones he'd taken from the other players in the area so I ended up with a lot of extra outposts (and somee xtra colonies), but still...