Part-timers, temporary help and even consultants may be necessary to the modern organization, but they are not the future. What companies want most now is stability. This is not a model into which temps and freelancers easily fit. Of course, that doesn't mean these companies expect that the person they hire today will stay with them forever. They know that many workers, white and blue collar alike, expect to move on to new jobs and new challenges once they have mastered a specific position and exhausted the chances for upward mobility.
Most firms are satisfied if a new hire lasts four or five years and moves up one or two levels.
That sort of mobility rarely poses a problem for business. In an era of rapid social, technological and economic change, few companies have any ability to plan beyond three to five years, so it would be hard for them to concoct long-term career plans for even their top people. Actually, in an era of so many mergers and buyouts, CEOs themselves can have little confidence that their positions will be around in five years. I know of one president of a Canadian subsidiary of a U.S. multinational who only learned that his company had been sold out from under him when he read about it in the paper. There's just no guarantee that the status quo will continue forever or that the company career ladder will be there for you to climb.