I was going to make a comment but it ended up a bit longer than that.
I am in agreement with others in saying NO. Unreleased things are not appropriate for Stack Exchange sites. While it is true we strive to be a place for answers, we are really not qualified to be the definitive source on any piece of unreleased product or future implementation.
However, I disagree with the reasoning that it is due to lack of expertise or the possibility of it changing. Gaming is one of those fields where things change quite often. Example, the first released version of games like Minecraft or DOTA 2 were quite different then their current version, not even considering alphas or betas.
To start off my argument for why this question is not accepted, I need to first point out that having an answer does not make a question acceptable. Questions must stand on their own. That is not to say that all questions are valid, but having an answer does not necessarily determine the validity of the question. If this was not the case, then in order to ask a question, a user would need to know that the answer exists. In such a case, every question would show a lack of research effort.
So, onto the issue of unreleased products. First up is the issue of where the information is most likely to exist. Who is the most likely group to have this information? Other gamers? Game Developers? Hardware Manufacturers? In most of these cases (if not all), gamers will not be the highest authority (at least until after gamers have access to it).
So say they do come to gamers. How will Arqade be able to answer such a question? We can speculate (bad) or look at other forums speculating (also bad) or check out what the developers have said. Now if we go to the developers, then how is that any different than the OP just going there? Additionally, if and when the answer changes, the developer's info will change first. So our option then is either continually update until release or have an answer that is just a link. Neither is a desirable result.
Second point involves our desire to help future visitors. Asking about unreleased products is usually not going to be helpful in the future, however in this case it very well could be helpful. However, without access to the system, we have no way to test it either way. Until then, our answers cannot help future visitors in a definitive manner. As an example, say I asked "What are the differences between the difficulties in the game Destiny". Arqade cannot play this game and therefore cannot answer this and even if we could, it is not helpful to anyone until after the game is released.
One final reason why questions on future releases are not allowed is to avoid users just looking for rep or badges. I could easily ask about different difficulty settings for every major future release and I'm sure after the game came out I would gets lots of upvotes. I'd probably also be the one credited with creating the tags for all those games as well. This is a scenario that we would like to avoid as much as possible. The purpose of rep was to award users that ask good questions and, more importantly, give good answers.
So does this mean you cannot talk about future releases? Of course not! Go to the chat and talk with your fellow gamers about whatever you want.