So how does this game compare to EUIII? Opinions?
Compare and compare, both games are fantastic. CK2 has a fresher feel to it, and the entire focus on persons and dynasties is always nice. I find CK2 deeper than EU3, but EU3 got a better trade and production system (CK2 got nothing like that, except for cash farms that you buy with money).
Seriously, buy CK2. Or try the demo. The demo is essentially the full game except you can only play for 20 or so years and you can not save. You can also only play 4 factions. Of course, you can easily glitch your way past the 4 faction thing (Just after you press play, chose another faction and you will play as that instead), you can also mod your game to start [insert number here] years earlier and then play all the way until 1086.
Best demo of the 21st century.