The Ender Saga is a magnificent piece of work, I have just concluded the series, literally closing part 4, 'Children of the Mind' just a few hours ago.
Speaker for the dead was the first of this series I read, my English Tutor introduced itt o me, recommending it as a thoroughly good read. I can't say I was dissapointed. In fact, I'd say it ranks amongst some of the best science fiction I have ever read.
As I read Enders Game after I read Speaker for the Dead, I can't really comment on how it feels to approach this book as a sequel, but I can say that having read this first allowed me to understand and sympathise with the Ender character of 'Enders Game'- brilliantly on my first reading.
Speaker for the Dead has us catch up with 'Ender the Xenocide' - Andrew Wiggen, who through the effects of space travel and relativity, is still living 3000 years after the events of Enders game. Though initially this story isn't about him, but a world where the galaxies only other sentient species since the buggers were destroyed, has been found. I read this story not even knowing their was a prequel/sequel and I couldn't have enjoyed it more.
It is inspiring, dealing with a whole multitude of characters and events, encompassing religion, humanities dealings with meeting an alien race, human conflict, everything, not to much nor too little.
I've read the entire Ender Saga and Speaker for the Dead definitely remains my favourite of the four, it is literally a different style to Enders Game, though the sequels to this book seem to follow suit.
I recommend this series, and especially this book, to any serious fiction fan, to any one who loves to read.