My first ToA game is done, and I am very happy with the expansion.  I did notice a couple of very small bugs, mostly concerning GNN construction reports, but nothing that took away from the game.

I played as the Terrans, on a large map set to challenging.  I got three Ascension crystals fairly early, and decided to try out the new victory.  Shortly after, the Thalans declared war on me, citing my interest in the crystals, and what had been a pretty laid back game went all to...well, wherever bad Drengi go.  I got kicked around by the Thalans and Altarians for a bit, made peace, got everyone else to attack the Thalans, resumed the war, got pretty things, ect. ect. 

Long story short, about 100 weeks from Ascension Victory I had managed to create a scrappy little armada that just might stand up to the concentrated attack from the remaining civs that I knew was coming.  By 75 weeks I was feeling pretty good about things.  Fifty weeks til victory I was getting antsy.   Week 25 came and went, and nothing.  I wasn't the most powerful civ, and most everyone was pretty peeved that I was doing the whole AV thing, but no attack came.

I won.  Great game, great new stuff, but just a little disappointed at the end.

So questions:  Was it that I was only on challenging difficulty?  Do AI civs know your progress on this victory type? 

Thanks!