DO go for it.
Like a silhouette, online booking can feel scary. But it can also foster a sense of community and grow your salon. Establish recurring opportunities for an influx of clientele through your online booking system, like monthly manicures or Friday blow-outs. When it gets closer to prom season, host tutorials on how to achieve a fresh-from-the-salon updo. Anything will do: as long as you're building a rapport with a new face, it doesn't matter how they come to you the first time.
Above all, DO stay true to what works—DON'T abandon it.
Staying relevant is essential, but keep it in context. Great customer service is as timeless as Audrey Hepburn and her little black dress. Approach online booking as a way to augment what you're already doing well, and the rest will fall into place.
*Source: Beagle Research, Improving Service Businesses With Appointment Scheduling, August 2009