I'm thinking springtails. I guess we need something to show the relative size, because a termite would be big, and a springtail is tiny.
If they are springtails, they're harmless. They just lay eggs in organic stuff, and obviously there were some sort of eggs in some component of that soil. If you're using the soil for indoor plants, you'll probably want to get rid of them, but if for outdoors, just ignore them.
A drench with insecticidal soap will do the trick. Just put the soil in the pot, then before you plant, drench with the soap solution, let it sit for a little while then rinse the soap through with plain water and plant.
