Good Readers and Good Writers
I personally feel like the main aspect to being a good reader and writer is balance; the balance between being able to absorb what it is you are reading without it being completely laid out to you. Nabokov worded it as knowing when to curb your imagination and let the author take over. You have to have an imagination, yet the intelligence to comprehend where it is the author is going. The most crucial part of reading would have to be that ability to get lost in the story you are reading; however, in reading, it is also just as important that you are absorbing enough of what you reading to keep your imagination in line with the direction of the new world you are being shown. Going into a book with a pre conceived notion is dangerous, yet you do need some general idea of what is taking place. If it is a sci fi novel, your imagination needs to remain somewhere within that realm. If it is a factual based novel, you need to maintain some realistic notions of what is going to happen.
This also incorporates into being a good author, because you have to have the skill to keep the readers somewhat contained in the possibilities of the story. Yes, create this new world for them, but it has to make sense. They have to have faith in your consistency of writing. If things are sporadically changing and straying away from the original point, a readers imagination is going to wander, and the author will have lost control of his own story. :)
Found this article orginally on The Huffington Post. :)
