Long story short: EP first edition was great, EP second edition is even better.
It's a complex but much more elegant game now. No rule feels more complicated than necessary in this edition, but all nuances and flavours of the 1st edition are still here. Pools especially are a neat and exciting mechanic, clearly introduced to ease the 1st edition's crunch. Skills have been streamlined a little bit, too. The writing is very good throughout and the typesetting is amazing. I have never seen a cleaner, more neatly put together RPG book before. It's the same timeline and setting as in the first edition, so 99% of the 1st edition books are compatible with this one and the remaining 1% is easily convertible.
I really have no gripes with EP2 apart from quite a few typos, but that's just cosmetics and has improved significantly since the version 1.0 (we're currently at 1.3). This easily is one of the best RPG rulebooks out there, my experience as GM being with Warhammer (1,2, 4), DnD (3), Fading Suns, New World of Darkness (Vampire, Werewolf, Promethean), Call of Cthulhu (7), Tales from the Loop/Things from the Flood, Vaesen.
I could now proceed with praising the game world and how fascinating its intricate structure is, but the following quote from the book sums the whole up better than I ever could:
Eclipse Phase is an exploration of uncertain futures. This is more
than a tabletop roleplaying game, it’s a detailed science fiction
setting that thoroughly investigates issues that affect our future as a
If you like gritty, bold science fiction, this is as good as it gets. It's where hard science, politics, sociology and philosophy go hand in hand to help you create the best sf stories possible.