I'm a paying customer and I have the right to bitch, complain and moan all I want. I spent money, not to mention time and mental energy, on Martin's books and I certainly wouldn't have done so if I didn't feel that there was at least an implicit promise that he would make a reasonable effort to finish the series and not leave me hanging out to dry with a thousand cliffhangers.
I understand about missing deadlines and writers block and all that. But if you can't write, then at least shut up about it, for Ghu's sake. Don't tease me with updates about writing and the possible finish of the book and then go, "Oh well, didn't finish. Off to Spain for a month".
It's not like I've been hanging around, doing nothing, waiting for the next book to come out. In the time since Feast Of Crows came out I've managed to get married, have a daughter, buy a house and do a lot of other cool and interesting things. Still, I check in on the GRRM site every couple months and I am happy to bitch about the subject when it comes up in conversation or online.