I seem to recall there was a question recently about handling multiple interrupts in a sketch. And I also recall that Crossroads pointed out that by judicious use of diodes you can connect multiple switches to a single interrupt pin (eg, pin 2), in addition to being wired to their own unique pins.
That way, with minimal effort you first get an interrupt (as all switches are connected to the interrupt pin), and then you just check by reading the other pins which one must have changed. The diodes stop cross-talking between the switches.