I dont think the + format will be around for much longer, all the companies that make the -r discs are trying to crush the market on the + format, even sony who was one of the creators of the + format along with philips make machines that read and write the - format.
+ is the Betamax of the VHS world, Better quality but more expensive and in the end will loose out to the cheaper and more massmarket - Format.
Thats all until the bluray machines come out anyhoo :P