Well i felt i had to add the text side of Sci-Fi. Too bad for me i ahve 4 series that are identialy at the top of my list.
Honor Harrington Saga [David Weber] - A Space naval series, it sticks to reality and tactics, and is an exclent read.
Known Space Series [Larry Niven] - Never before has such a coherent series of different tales been written by ine man. Charecters encounter each other, Mystery, drama and intruige, its got it all.
Miles Korvosigan Series [Lois Mcmaster Bjould] - Beyond descrition, the charecters and universe are too perfect. Follow Miles as he grows from a military dropout to a high ranking government offical.
Engers Game, Xenocide, Enders Shadow [UNK] - Yu all know this, no need for me to explain.