One other question for native speakers: Do the points discussed above also apply to NEGATED future constructions, or are the rules a bit different if there's a не accompanying the verb? (After all, in a negated construction, the action is "non-completed" in any case!)

For example, as I understand things, if one wanted to say I won't have read (="have finished reading") this book by Thursday, then the choice of aspect would be clear -- future perfective is mandatory:

Я не прочитаю эту книгу к четвергу.

But when there's no specified time of completion, and one simply wants to say "I won't read the book," is there a difference between the following two?:

Я не прочитаю эту книгу.
Я не буду читать эту книгу.

I would interpret the imperfective construction as emphasizing "I am determined to never read this book under any circumstances" -- in other words, a negated imperfective future has some implication of никогда, ни за что!

On the other hand, I know that it's totally possible to use никогда with a negated future perfective (я никогда не забуду, for example).

So I'm interested to hear the opinions of natives about this.