That's a fantastic question!
First of all, it's kind of important to recognize where organizational change has come from. You can do a google search or hit Wikipedia for a decent overview of the field.
An interesting journal you might want to read to find out more is the Administrative Science Quarterly is a scholarly journal that focuses on the field of Organization Studies into which Organizational Change falls fairly frequently.
As far as what's on the horizon to tip the apple cart, as it were, I'm particularly interested in the effect of generational change and cohorts, and I am doing research on how companies are preparing to deal with it.
That is, each generation has particular characteristics- you've heard of some of the Baby Boomer's aptitudes and tendencies, as well as Generation X-ers. The Millennial generation has just begun entering the workplace, but much has been written about them also. The newest generation has just started to be born, and has been referred to as the Homeland Generation.
Each generation is, essentially, influenced by the generation that reared them. By and large, Gen X was raised by the Silent Generation, with an overlap by Baby Boomers- but the generation was raised in the immediate aftermath of Vietnam and Watergate, and was the product of a society of divorce and latchkey parenting. As a result, they are protective, pragmatic, and survivalist.
Their predecessors, the Boomers, were visionaries (think of the 60's and 70's). They have a very different style, but it is noted by a tendency to long-term commitment to the employer.
Millennials were raised by a much more protective, child-focused era, and have different attitudes which include a heavy focus on teamwork and collaboration, and they expect the workplace to change to meet their needs.
There's a great article in the current Harvard Business Review that overviews the full picture. (The Next 20 Years: How Customer and Workforce Attitudes Will Evolve) http://harvardbusinessonline.hbsp.harvard.edu/b02/en/common/item_detail.jhtml?id=R0707B
Back to your question, though, one of the major events that may shake up organizational change is the so called "Boomer Exodus." That is, within the next 10-15 years, millions of upper and middle management Boomers will be retiring. Not a major problem in itself, until you consider that there are 20 or 30 million more Boomers than Xers, and that they've held these middle and upper management jobs for a long time. Xers, by and large, haven't deeply penetrated those positions yet, and there will be huge vacancies ahead. Millennials won't have the experience at that point, by and large, to fill the posts, either.
If there's anything to this Boomer Exodus theory, talented and well-trained Xers will have a tremendous opportunity to move to companies that have lots of perks and benefits, but the Xers will really have the upper hand to pick and choose the workplace they want to lead. Organizations are by and large not preparing to address this and create the loyalty that isn't there.
If your organization has some really well-trained Xers, it would be worth it to develop programs to ensure that they are loyal and have attachment, otherwise they could flee to follow the money. Managers need to look closely at how they measure retention and how they are working to ensure productivity from the workforce from the Millennials on through the Boomers.
On the scholarly side, the field of OD is going to continue to struggle to find itself. Right now, it is largely overlapped by business programs, sociology, and organizational psychology, and it is struggling to find itself. It will be interesting to watch as the internal battle wages and as the field either emerges as an independent discipline or whether it is subsumed by management practice and study or one of the other fields.
I'd be happy and interested in talking more, and I'm curious about where your question came from- are you in school now, or are you a practicing consultant?