There seem to be two types of audience when dealing with fiction that may not necessarily be to their liking or "fit" with their interpretation. One staunchly resists it, refusing to accept or just plain getting angry. The other tries to consolidate what happened into the universe, offering conjectures and theories, none of which have much basis in the story and are mostly based on circular reasoning (only true if you're thinking it's true as you're reading it). I count myself in this latter category, and is probably a reason why I like fan fiction so much.
For example, in Buffy the vampire slayer, there's a lot of controversy over how slayers get selected. There can be only one every generation, but there appears to be hundreds of 'potentials' floating around, that get called when one dies. Much head-explodiness occurs. Lots of questions here - who 'calls' potential slayers? How are they chosen? Is it every generation or is there always a slayer? What happens at the end of the series when all the slayers are called? Some people get angry that these questions aren't answered. Others try and justify it either using evidence from the series (light as it be) or just saying "character mistake". (Note: This isn't like Rinoa = Ultimecia, where people are trying to shove something in that doesn't belong there. In that case, there's no unanswered questions and no unsatisfyied promises. This just people trying to shove something into an already full bucket).
In the Dark Tower, there's controversy over the fact that a leading villain throughout the books is killed quickly and easily by a new character. And then that new character, the son of the hero and prophecied to kill him, rarely appears at all throughout the rest of the book, and is killed quickly and easily by the hero when the confrontation occurs. But people who supported this attributed it to the leading villain's waning powers and gave the son more credibility quickly. Other pre-existing material was ignored or retconned. Family members change names frequently. Plotlines were unfinished. And characters weren't used as they were foreshadowed to. Some interpreted this as just part of the story, saying that not all prophecies were fulfilled. Some were angry that questions they expected to be answered and fleshed-out were not.
As a reader I side with having all promised questions answered. As a writer, I can understand the difficulty of keeping them all straight through a seven book series spanning twenty-two years. Especially a writer like King who writes so organically that sprouts and buds grow too fast to be trimmed. I think it's important to write everything that needs to be written down, and it's bad writer karma to include things that aren't going to be expanded on. We have no idea what happened to Roland's friends at Jericho Hill, or why it happened, and that's the answer I was most looking forward to, but didn't get. But I don't get mad, I just believe that the story didn't call for that plotline to expanded, and there was no place for it in the main story. So I guess my advice to you is don't write checks your ass can't cash.