Cracks in acoustic guitar tops are either caused by trauma, or dry wood due to low humidity. If the guitar has been stored in a very dry climate (<40% humidity) for a long time, the top may crack. The inside of an acoustic guitar is not finished since the finish dampens the resonance of the body. This makes them very susceptibe to changes in humidity. Whoever repairs it, make sure they know how to assess the wood for dryness, and will correct the moisture content of the wood before repair if necessary. I have seen dry guitars with cracks that virtually disappeared once the wood was properly hydrated. I can't see the crack on yours well enough to tell what may have caused it, but the bottom line is that it is worth investigating why it cracked before repairing. If you already know it was traumatic, or can see evidence of trauma in the area of the crack, then disregard this.
