By the way, the general wisdom is that a hardware switch needs to be de-bounced. If you connect the switch to an interrupt, then expect the interrupt to be called multiple times within a few milliseconds so you need to handle this situation.
A search of the internet will show you many of the hardware and software ways to de-bounce a switch.
While this might not be an issue with the switch simply turning on a LED, if the requirements change slightly - to, say, having the switch toggle the LED - then you will get very erratic behavior until the switch is de-bounced.
Susan