I've been playing it a bunch. Overall I'm really impressed. Essentially the game is Europa Universalis but in space, oh and way better in just about every way. I usually spend a TON of time in EU on pause dealing with redirecting armies or reading text or trying to figure out what I'm supposed to be doing. Not so in Stellaris, I mostly spend the game chugging along exploring the galaxy or trying to figure out if I'm ready to launch a new war or tweaking planetary setup. The AI seems much improved as well, it doesn't just declare war constantly like the EU ai did. I even played some multiplayer with a friend yesterday, it surprisingly turned out to be a fun experience. Usually those realtime games are slightly infuriating to play multiplayer because someone is always pausing, but Stellaris seems to be in a great spot where there wasn't any need to pause.