Yes, they probably will. A recent study conducted at Queen’s University Belfast reported that students are more likely to view the availability of recorded lectures as a reinforcement of class teaching, rather than a replacement of it.

In a post-course survey, 96 per cent of students said that the availability of footage had had no impact on their attendance … [and] 98 per cent of students said that revision in preparation for an exam was a primary reason for viewing a video.

A brief summary of the research published in the THES is available here.