You should be concerned enough to always keep an eye on it just like your sump pump, etc. If it looks ok then don't let it affect the sale unless you want something knocked off the sales price. Ask the homeowner who did it and talk to the contractor. See what the warranty is on it, etc. You could build a new house tomorrow and still run the possibility of having cracks in it.
As an aside, we used to make fun of this texan who put soaker hoses around the house in dry weather and then I just heard on the news last night about a house foundation (it was brick and not a basement) that cracked from the effects of drought on clay soil and the newscaster was telling everyone to soak around their foundations. So go figure.