If there is a flow on just make sure you leave them enough supers especially if you are going to be gone a while so they don't run out of room.
As Sparky said you could put out bait hives just in case they swarm while you are gone.
The beauty of keeping bees is that they are much more independant than anything else you can raise, they feed themselves, put themselves in at night, defend themselves pretty well, clean up after themselves and don't make much noise... the perfect pet :-D
If you need to be gone for an extensive time you might be able to find another beekeeper to peek in on them otherwise go have fun!