Well, I just finished speaking with Panasonic. As it turns out, it was the backlight. Labour, parts and shipping will cost me under $275CDN, which isn't too bad. Far cheaper than getting a new laptop.
I'll have it back Wednesday, thankfully. The poor SO has been driven mad by my needing his laptop. He's been good about it. Perhaps a couple of dozen of Mr. Felix and Monsieur Norton freshly made cookies will be in order..