See EUOL's blog for a very interesting hate mail he recieved.
http://brandonsanderson.com/blog/632/Reader-MailI love it when people totally blow things out of proportion. That reader strikes me as some one who is probably between 13 and 16 maybe 17.
To opine on EUOL's comments.
1) Well said. Look no further than the book (and movie) "Neverending Story." The whole premise is that the stories have no start and no end, just places and times where we join and leave the story.
2) It is called set up. The loose ends not only let the reader imagine what the characters do next, but they allow the author a springboard for any sequels should the book sell well enough. (And Elantris has by all measures.)
3) WE (the readers) would love to see a sequel. That being said, it needs to be done in the time and matter so as to preclude those unbalanced readers (i.e. the sender of the hate mail) from saying it was rushed and it sucked and they aren't going to read EUOL's books anymore.
4) Bingo!!!!!
5) Can't wait for my book to come out. (A side note to EUOL, you gotta make me and my wife, who hates all Fantasy/Sci-Fi books except yours, alpha readers. Please!!!! I even give you my kid's college fund if you do. Granted there isn't anything in it yet, but it is yours none the less.)
6) Nice shameless plug!!