The Spanish site Meristation Juegos PC published a preview of Civ5 today,
you can read the Google-translated article here.
The interesting part is about the much debated combat system:
"The units may “pass through” squares occupied by friendly soldiers,
but they can not stay in the same area, or join forces.
Yes you can put in a box two units of various types,
eg. a military unit with a worker who is working in the same area, “but that’s all.”
Origineel Artikel: http://forums.civfanatics.com/showthread.php?t=360540&goto=newpost