I love Jim Raynor. His personality reads a lot like Mal from Firefly and I love Mal too - the tormented criminal with the heart of gold. I wasn't sure what to expect from Heart of the Swarm (The Starcraft 2 xpac) but so far I absolutely love what they have done with the story. Someday I really need to play that character in a tabletop RPG!
The key to the bit is Kerrigan's motivation. Why would she go back to being the Queen of Blades? What is she doing on Team Zerg again? Raynor rescued you, fool, why are you going and messing everything up?!? They did a great job making that switch work though and it reads like a tragic love story with the twists based on misunderstanding and mistake. A little bit hackneyed and unoriginal to be sure but the best plots have all been done before so all you can do is try to do that same old thing well.
The mechanics of the game seem really solid too which I appreciate. It is more of the same from SC2 with timed missions, crazy events to deal with, and new mechanics on nearly every mission once you get past the intro. Pretty much they took the original campaign (which was great fun) and did the same thing again but with a new plot, new race, and everything shifted enough to make it great. Nothing spectacularly innovative, just solid execution and polish which is what we have come to expect from Blizzard.
Thankfully HoTS bucked the trend of big titles bombing on launch day because the servers weren't up to the job. Downloading took a little while and things were a mite choppy now and then but for a launch day experience it was excellent. I played the game, it was tons of fun, the game worked as advertised. I am sure a week after launch things will be smooth as anything because all the downloading will be done and the rush will have slowed a bit.
I should note that I haven't beat the game yet and am probably only about 1/3 of the way through. I started out on Hard which seemed very appropriate - I am rusty as hell but I only died once so far though I had my share of close calls. Clearly I will need to get better and practice up to beat Brutal but it should be quite doable; from my vantage point they got the difficulty just right. Maybe my mind will change after beating the game or actually testing Brutal but so far Blizzard gets a massive thumbs up - HoTS is good stuff.