The National Academy for Engineering has been trying to identify the grand engineering challenges for this century. It obviously features several challenges in environmental sciences, artificial intelligence an virtual reality. I was very pleased, and slightly surprised, to also see Advance personalized learning as one of the grand challenges.
While the explanation seems to start of with a bit of a disappointing focus on learning styles, it then picks up with applications that I find much more interesting, such as tailored support to learners based on ubiquitous data collection of their progress. I am not quite sure this is an engineering challenge though. 99% of the technology that is needed to meet this challenge already exists. It is primarily our inability and sometimes unwillingness to implement this properly that makes it a challenge.
A good start could probably be made in the education of those who are going to be delivering this personalised learning. From what I recall from my various bits of formal teacher training, the emphasis was on a rather old fashioned model of learning. I was taught how to teach, but seldom did we learn how people learn.
A second area that needs challenging in my opinion, is regulations and management. In most institutes I have worked for, innovation was strangled by conservative financial management (where risk is a dirty word, and profits are always expected in advance to cover investments... a very peculiar idea). In many areas professional bodies also seem to work more to the detriment then the benefit of innovation. The message there often seems to be 'do as we have always done, and you'll be alright'.
Personal Learning definitely is one of our great challenge. But the challenge is not to invent it, or make it technologically possible. The challenge is 'simply' to implement it, and make it work.