So this is the third cirque du soleil show that I've been to in Vegas (in addition to O and Mystere), and while I was still very impressed with the performers, it is my least favorite of the 3. This is mostly because I don't feel like there was a clear storyline or theme.
Zarkana is located in the Aria, which can be reached by taking the little sky shuttle from Vdara/Bellagio or through the Monte Carlo walkway, if you so happen to be staying in any of those hotels.
I don't want to spoil it for others, so I will just say that my favorite act was the two fit blonde guys and their aerial ballet. I don't know what to call their act, but they make it look so easy and they're very graceful, so I think ballet is an appropriate term :)
Unfortunately, while I think the performers were very talented, I probably would not see this show again, whereas I would go see O again someday (pricy, but so great!).