First it was music. Then it was theater. Now it's...education? Technology has enabled inexpensive reproduction of a wide variety of media, which has in turn radically transformed the structures of a number of industries. Whereas we used to have only concert halls and live theater, we now have CDs, MP3s, DVDs and movie theaters, and industries that used to consist of a large number of moderate-scale performers are now mainly served by the Brad Pitts and the Lady Gagas of the world.
Economists refer to these sorts of industries as "winner-take-all" markets since their key feature is that a few "superstars" serve a large portion of the market (and often receive astronomical payouts for doing so) while a long tail of similar, somewhat less-qualified or less-talented individuals see comparatively minuscule levels of success. This phenomenon is seen clearly in the markets for actors and musicians but is also prevalent in professions such as writing, banking and sales.
The traditional model of education is not altogether different from the old-time theater or concert model. On the up side, customers enjoy a live experience where they can potentially interact with the performer or instructor. On the down side, this model is limited in its scalability (especially where simply increasing venue or classroom size is not reasonable) and thus more expensive than its virtual counterpart. Given the skyrocketing cost of college education, the potential appeal of virtual instruction is becoming quite significant.
In order to evaluate the benefits versus costs of virtual instruction, it's important to understand how such a system would impact student performance. Researchers David Figlio, Mark Rush and Lu Yin were able to shed some light on this issue by running a controlled experiment. In their experiment, students in a large introductory economics course at the university level were randomly assigned to either an in-person or an online scenario (much like a clinical trial in medicine) and the performances of the two groups were compared. They find a modest positive effect of in-person instruction, but this difference of a few percentage points doesn't stand up to a formal test of statistical significance, nor is it likely to make a material difference in students' educational outcomes. It is, however, relevant to note that the measured positive impact of face-to-face instruction is more significant for Hispanic students, male students and low-achieving students. (In case you're curious, I emailed the authors to inquire about instructor gender, and they told me that they used a male instructor.) These findings are in contrast to an earlier U.S. Department of Education Study that surveyed existing literature and found that the effect of online learning is positive when compared with face-to-face instruction.
This experimental methodology is certainly appealing from a research standpoint, but it doesn't accurately represent the educational trade-off that schools face. Just like in music and movies, technology makes it possible for a large number of students to be served by what are likely to become "superstar" instructors. Therefore, in order to truly study the effect of moving from an in-person to a virtual learning environment, one would have to compare the outcomes for students taught in a virtual setting by the best instructor available to the outcomes for students taught face-to-face by instructors of varying quality. It's hard to dispute the hypothesis that the higher instructor quality would likely overcome the modest benefits of face-to-face instruction, and I would be willing to bet that this form of virtual instruction would come as a welcome change for those students taught by instructors who are teaching merely to fulfill university requirements, are using courses to push their own agendas, or just plain don't speak English. (I mention this last point because it's the most frequent criticism that I hear from students...though not about me, thankfully.)
Virtual instruction has the potential not only to give a large number of students access to top instructors at lower cost but also to provide the incentives to attract and retain top teaching talent in the first place. Teaching is a very labor-intensive and often thankless profession, and people who are good teachers frequently have skills and talents that help them excel in more lucrative careers as well. The potential to become a "superstar" instructor could give talented teachers a reason to stick around in the education sector and hone their craft. I doubt these instructors will reach the level of wealth or fame of Brad Pitt or Lady Gaga, but hey, it's something.