Video analytics is a vast and potentially limitless technology. Ultimately, humans are highly visual creatures, and until a machine can "see" everything a human being can, there will still be room for development. Though much of the video analytics business is today focused on surveillance applications, ultimately I believe consumer applications will come to dominate this field.
Already, low-cost video analytics applications have found a home in digital photography in the "smile detection" feature that waits until everyone is smiling before taking the picture. Consumer home security applications -- which I would put in a different category from government and big business surveillance -- are now taking off. Though privacy concerns are obvious, as mentioned here previously, set top boxes that can identify who is watching the TV have been developed (see Targeted TV commercials). TVs that can be remote controlled via hand gestures are in the works. This is all just the beginning.
Eventually, perhaps when today's Internet-generation kids become grandparents -- perhaps sooner -- people will have enough trust in technology that they won't mind having numerous consumer devices "looking" at them all the time, not to spy but to perform useful services. Even perhaps the most mundane appliance -- the toaster -- will be revitalized as the smart toaster that can see whether you're putting sliced bread or bagels inside, and toast accordingly.
Economies of scale will need to kick in before smart toasters become real, of course, but the video analytics revolution is happening already.