I called up Magazine Billing Services today when I got home from work in hopes of straightening out the 10-year subscription issue. I was ready for a fight. I had my pen and paper on hand, ready to take notes and names/ID numbers of CSRs who wronged me. Aaaaaaand, I didn't need these things at all. When I called, I talked to a CSR named Sharon who was very friendly and helpful. She explained why cancelling the subscriptions was difficult and had a charge associated with it (because they have already paid the publisher for these subscriptions and wouldn't get refunded for them), but suggested that we transfer the payments I'd already made to other magazines (which I hadn't even thought of). So I ended up renewing Cooking Light for 3 years, and Games magazine for 2 years (as well as keeping one of the three year renewals to World of Puzzles). When she asked if I had other mags I'd be interested in transferring the subscription to, I couldn't remember how much I had left on the subscriptions I already had, and she said she'd find out and call me back. Which, she did. Promptly. Everything was quickly sorted out, and now I've got a reasonable number of years on all of the magazines I already get, not 10 years on one (that may not even be around in 10 years - thats what happened to me with World of Crosswords, which I used to get and loved. It disappeared halfway through my subscription and was replaced with a far crappier monthly crossword magazine).
It was such a strange and unusual customer service experience, that I'd recommend that anyone handle their subscriptions through Magazine Billing Services. Wow. I totally did not imagine yesterday that I'd be saying this today.
Oh, also - I did ask that they remove my name from the mailing list to prevent this from happening again, and she did that too, happily. Love!