We know that the game will most likely have three teams per alliance because of 4.5.1 in the administrative manual. "Practice matches are randomly assigned and each team is assigned an equal number of practice matches unless the number of teams multiplied by the number of practice matches is not divisible by six."
We know that the field will most likely be rectangular, because of AndyMark. "FIRST® has determined that this Field Perimeter has the ‘fit and function’ necessary for use in the 2015 FRC."
Link:
http://www.andymark.com/Field-p/am-2800.htm
What will be the significance of "change is coming?"