While Orwell was a self proclaimed socialist and even participated in the spanish civil war and wrote about the spanish socialist communities of that time, he is viewed as a mere traitor by many modern socialists.
I know that he handed a list of socialists (and gays?) to the british government. But do we know why he did that? And what exactly happened to the people on the list afterwards?
The list is in the Public Record Office and was released to the public in 1996. It contains people Orwell thought would be unsuitable for anti-communist propaganda. He wrote it in 1946 to his friend Celia Kirwan, who was working for the Information Research Department of the Foreign Office. This was at a time of intense Soviet infiltration of Western cultural organisations and events. Orwell had turned anti-Communist after witnessing their ruthless suppression of fellow socialists and anarchists during the Spanish Civil War. The Soviet Union was not a beacon of socialism to Orwell but a repressive regime. He remained a democratic socialist until his death.
Source: Orwell's entry in the Oxford Dictionary of National Biography.