Well, it took less time than many other people seem to have reported on the review sites I've found, but I finally received my refund from Magic Jack. It was credited to my account this morning, and I was thankful to see it finally arrive. I didn't want to have to keep fighting to get my refund.
I will soon be updating my complaint with the Better Business Bureau to let them know that I did receive my refund. So (finally) ends my battle with the un-Magic Jack.