Earthworms make up a substantial portion of a centipedes diet. I kill every one I see!

Worms only make up a significant portion of the diet if worms are the most easy to come by. They're main diet is that of other arthropods. In fact, they take out so many bad insects that they are considered a beneficial in the garden. Centipedes tend to stay at the surface. Ever notice how they are most prevalent in the few inches of outer edges/surface area of your compost even if it's cooled (assuming adequate moisture).

In a worm bin they eat worms mostly because worms are the easiest catch and by far the most prevalent animal (aside from the hardly worth hunting mites and springtails). They eat tons of insects and other animals in the compost pile. I have compost worms and centipedes in my compost heap. The centipedes don't seem to be hurting much of anything. I don't allow them in a worm bin, but I don't have any problem with them in my compost bin.

Did you also notice along with the increase in centipede population there was a roly poly population increase?

The centipedes are attracted to the moist environment of decomposing matter. They need the moisture to survive and the decomposing matter attracts a smorgasboard of prey. I'm of the opinion that killing centipedes in anything but a worm bin is a really bad move. There are a multitude of possible reasons for a population increase. One, the most likely, is the warm weather. Two, an increase in the population of other compost dwelling arthropods. Three, you're getting even better at managing your compost. Plus plenty of other possible variables.

"Three, you're getting even better at managing your compost."

Thanks for all the answers- but the above one I really like!!