Often when something goes bad, it's a smart strategy to take a look at what went wrong to learn from those mistakes. In a similar vein, it's important to look at successes and learn from them as well and there is no denying that Toy Story Midway Mania has been a huge success. I would venture to say that it routinely has longer lines than even Soarin and if you measure success by guests who try to see it, then Toy Story Midway Mania is the Babe Ruth of rides (that means it's really, really good).
If we take a deeper look at the attraction, I think we can learn a few lessons that can be applied to future attractions that will come to the parks.
With it now being 2010, for a while it kind of seemed like the days of the dark rides were fading fast. The Magic Kingdom (and Disneyland) were built initially on the backs of dark rides such as Snow White's Scary Adventures, It's a Small World, Peter Pan's Flight, et al. These sort of rides were the backbone of the parks in the beginning but with technological advancements and a changing appetite of guests, it seemed like guests wanted rides that were more intense and/or engaging. With Toy Story Midway Mania, we see guests still love their dark rides and they can be just as entertaining as any complicated and advanced simulator, coaster or show.
An unique aspect to Toy Story Midway Mania is the fact anyone can ride that wants to. There are no height or age requirements and even those with conditions like bad backs or being pregnant can enjoy the ride and that's important if you want a ride that will be popular. Once an attraction has limits as to who can ride it, it starts limiting even more people from being able to enjoy it because those affected by the ride limits will likely cause others not to ride. Think about it, if someone in your group has a bad back or is too short to ride something, often your group will simply skip the attraction because it's not fair to make that person(s) wait. This is especially true of thrill rides where families just can't have their younger children wait around for others to ride. Because Toy Story Midway Mania allows even newborns to ride (in their parents lap), there's no cause for concern about leaving someone behind.
I think after the failure of Mission:Space to catch on as a headliner attraction, Imagineers may have rethought the notion of implementing really cool, bleeding edge technology into an attraction. Since high tech stuff typically costs a lot more than established technology, there's a greater invesment to be made but with Toy Story Midway Mania, guests really enjoy the 3D video shooter that is clearly a step (or two) ahead of any shooter we've seen before. After playing Toy Story Midway Mania, riding an attraction like Buzz Lightyear's Space Ranger Spin seems like the theme park equivalent of playing Pong. While an attraction that is big on technology like Mission:Space didn't work, new attractions can use technology and still be popular but given the previous lesson of the importance of including everyone, that new technology should be able to include rather than exclude.
Not everything about Toy Story Midway Mania is perfect and if there's a problem with the attraction, it's that it loads way too slowly. Given that it's a dark ride and everything is sequenced together, the ride should be able to move many more guests per hour than it currently does. There's no facts or figures out there to evaluate, but it just seems that it takes longer at Toy Story Midway Mania than at other dark rides. This problem became apparent when Disney pulled the plug on the single rider line because, among other things, was not helping with the flow of the line. Obviously it's incredibly popular, but future attractons should not only be cogniscent of the first three lessons outlined here, but ensured that as many people as possible can enjoy it.