Further dates are as yet unknown.
It will be including characters from all branches of the Marvel Universe though. Suggested to appear so far have been the mainstays and their extended character families. This includes Black Widow, Hawkeye, Captain America, Thor, Hulk, Wolverine, Spider-man, Black Cat, upon many many more. The story seems to be centered around the cosmic cube that was heavily featured in the Phase 1 Marvel movies. X-23 appearing in this show is unknown as yet. They do have an extending claw rig for portraying Wolverine though. So it is not a far stretch that they could, but we shall see.
Videos from Marvel's Youtube page.
Meet the creators spotlight:
You can find out more about the stage show from their website over at MarvelUniverseLive.com as it is further updated. There is also a special about it over on HeroComplex at the LA Times that is well worth reading for an indepth look at how this came together. You can find the press release from there site linked here as well. The show is set to tour 85 North American cities starting as of July 2014.
Further info to come as it is available. It looks to be somewhat akin to the stage shows that were done for Mortal Kombat and Batman in the past that many fans praised. Possibly with a higher budget due to all the talent involved in producing this and making it all come together. It looks to be an amazing sight to see and quite the experience being brought to fans all over the country soon by Marvel and Feld Entertainment.
Personally, I look forward to hearing which characters have been included and the choices behind each as further details are revealed or announced.