Planning is esstential and normal for each serious project, so I assume Mark has this information ready.
I guess you're not familiar with The Agile Manifesto? Large scale planning is no longer an integral part of developing software.The reasons are many, but the most important one is that unlike traditional manufactured goods or building, constructing software is not something you can plan ahead, because you're trying to hit a moving target.
When you're building a house, you can be pretty sure that in the middle of production, you won't have to suddenly start adding a basement, or having to build it twice as wide, and half as tall. When building a car, you can be pretty sure it's not supposed to be able to fly aswell.
When building software however, these certainties cannot be taken for granted. Hardware changes, software changes, changes in what the user/customer needs/wants, competeing products etc. all combine to make software infinitly more complex than all other traditional forms of production.
Thus traditional engineering methods, such as those deployed in the past, are not effective at controling and managing quality software (as the huge ammount of absolutely terrible software available substantiates).