Yeah, I'm guessing your fantasy novels wouldn't go down as well in an audiobook scenario.
It depends, i'm also listening to R.A. Salvatore's Neverwinter Saga , and that works great. I guess it comes down to how much of the blanks you can fill in, too much new worlds, characters and concepts is probably the tricky part. Fantasy novels tends to throw alot of these things at you in the first half of a book. So with R.A. Salvatore, the characters tends to be well known, the world (Forgotten Realms) are well known and i got a general feel for the setting and why certain groups will hate certain other groups.
Now with something like GRR Martin's Ice&Fire Series (known as Game of Thrones) the first book is really hard on audio, but the 3rd book is much easier because you know the characters (those that are still alive anyway) and the world.
I would think Wheel of Time would be great on Audiobook from the 2nd book to about the 6th book, or round about where Jordan started adding more and more characters and deviating from the main story line and just went into random meaningless directions. So the last 5 or so books of Wheel of Time must be a total nightmare on audio, because you would need an encyclopedia to look up character names. Ironically, the later WoT books actually do have a index/wiki at the back to look up places/names .
I'd think Raymond Feist's books where he doesn't explain the entire world in one book, but focus entirely on ONE character alone (like The Magician) should be awesome on audiobook...actually i think i should look into that. There the fantasy world is secondary and it kinda gets explored with the character.
Steven Erikson's Malazan Empire, now that i got the audiobook and it's difficult, not impossible, but i've had to rewind numerous times when a new chapter starts because i have lost the plot, literally. Reason is, his focus is on the world and the factions and the history rather than any particular character (so there's , similar to Game of Thrones, a ton of characters).
So long story short, fantasy and sci-fi should be fine, unless the author is creating a very complex/detailed new world with a lot of character and actually setting this stage in the first book, then you need to concentrate . And when you need to concentrate that much, then it might be easier to just read it.
I do find it quite useful to sit on a plane, or anywhere where i feel kinda sleepy and just want to "rest my eyes" , to listen to an audiobook instead of trying to read.
I also love how characters become alive with a good narrator (and yes as previous poster said, the text-to-speech stuff is nonsense) . The catch is, audio books are more expensive than text books, due to the narration. However my subscription to Audible ($15 a month) gives me an audiobook which easily costs $30-$40 for the $15 (which is what a kindle ebook tends to cost). So it works out not too bad . You can obviously go torrent these things, but the syncing and bookmarking and all that can be tricky with the torrented stuff.
Oh and for the Koontz fans, here's the Odd Thomas Series nicely in audiobook format
http://www.audible.com/series/ref=hp_f_1_sa?asin=B005NAU59I
It helps reading the reviews, the people will actually quickly say whether the book is difficult to listen to.
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