In The Independent Andrew Johnson talks to other authors, including Robert Harris, Philip Pullman and Terry Pratchett, about it and about other reads that are particularly important to them.
(What are your memories of it? It's one of the books I've revisited several times since I first read it when I was at school in the '70's.)
Paul Owen on The Guardian blog points out that the plot was ... erm borrowed ... from Yevgeny Zamyatin's We, published in English in 1924, and which Orwell himself reviewed.
But maybe it's all right in the end. Johnson concludes :
... it is extremely doubtful Zamyatin's book would have come to fill the unique place Orwell's work now occupies. Nineteen Eighty-Four is an almanac of all the political ideas no "right-thinking" person would ever want their government to countenance, and the word Orwellian has come to signify a badge of shame intended to shut down any movement in that direction – with an imperfect record of success.