Trying to make objective arguments about something as subjective as a book is always a pain. That said, I'm in with J-Z-Jazzy-Dyal on this one. Martin had sex, sometimes graphic. Sometimes it was there to shock, or sometimes it was there to titillate, and almost always it was there to advance the characters involved. Goodkind has a whole lot of masturbatory torture.
I've only read Goodkind's first book, and only finished it because I had a massive fever and couldn't leave the house and had nothing else to read. It was, I thought, insultingly bad in some places, and very much *not* my kind of book. To be more specific:
Goodkind seems to be a writer very much into ideas. As ideas come quickly and easily to me, I am generally unimpressed by ideas alone. I need significantly more than just ideas to enjoy something.
His ideas are supported by characters who didn't work for me -- they felt one-dimensional and bland, and every once in awhile he'd try to inject some life into them by having them declare that they weren't usually so one-dimensional and bland ("It seems like I've done nothing but cry these past few days. I've always (not in this book) been so strong..."). So I didn't get character.
His images and setting were fantasy cliche without any depth drawn in. I recall being surprised when a given monster turned out to have arms, because he'd described it so badly that I'd been thinking "Wyvern" when he was trying to write "Ogre". As for his setting, I felt most of the time like Goodkind just wrote "castle" and left us to fill in the blanks. I never got a real sense of place. Mind you, this didn't bother me hugely, because I don't really get into settings... but if even I noticed it, that's bad.
His plot was inane. Foolish problem complicated by foolish decisions by the main characters, and a foolish result.
Needless to say, I didn't go for his sequels, so if he addressed some of those problems later, his other books could be decent.