I wrote this article for my website but thought I'd share here as well.
Please note that everything below is pure speculation based on everything I have seen in regards to the 50th Anniversary. So please don't put me in a time lock if it turns out to be wrong. I'll update as the moment nears.
I will be looking at the trailers in the order I think they will appear in the episode.
The Time War
Time Locked - The Moment
Due to the previous events we will be introduced to the Forgotten Doctor who is travelling to the hut we can see in the distance of the second picture. Where inside is the device we can assume causes the Time Lock. The Doctor attempts to push the Button/Jewel however it does not work. This is when I predict he will be met by a familiar face....Rose.
This is where I believe Rose talks to the Forgotten Doctor about the moment and possibly explains that he needs to find The Doctor to help him with this task. (more on this again later)
The Doctor meets Clara
Elizabeth and Ten
The moment - part 2
So that is my trailer breakdown of the 50th Anniversary trailer. I apologise if it doesn't make much sense. Let me know your thoughts, feelings and theories in the comments below. Have I missed something or went totally the wrong direction. Let me know!