This launch is the exact same as every single Total War release since this site went live, and the forum reaction is likewise exactly the same.
Some people can't play the game at all. Some people can't get more than 10 minutes in without a crash. Most people have to humbly crank down the graphical settings against their will (you mean I have to play at Ultra instead of Extreme?! Am I being detained?!), though some will get to crank them back up after some optimization patches and drivers. Many hate the new features and interface and identify the previous as the pinnacle of game design. Most are a bit annoyed at things in promo material not actually existing in game.
The forums are flooded with talk of how CA lied to us. Some threaten that this is the last Total War purchase they will ever make. There will be 101 lists of 101 Things we need fixed ASAP.
And at the end of the day most of us will still be playing and enjoying it because we love the series enough to
about it; I just wish more people did more of the former than the latter. The occasional useful thread helped me identify possible performance issues and bug workarounds while I was at work unable to play. Then when I got home I made the quick changes and had a blast for the rest of the night.
Soon there will be a slew of mods to choose from and in two years everyone will remember Total War: Rome II as the pinnacle of game design when Total Medieval War: III (yeah, that was a jab at your naming consistency, CA!) comes out with a bulky interface and a single rebel faction making expansion too easy.