Rags-to-riches romance "Slumdog Millionaire" furthered its winning streak in Hollywood's awards season, earning best adapted screenplay for writer Simon Beaufoy from the Writers Guild of America.

"Milk," about slain, 1970s-era gay politician Harvey Milk, grabbed best original screenplay for Dustin Lance Black who gave an impassioned speech challenging the gay community to re-energize itself in the struggle for gay equality.

Black talked about how Milk's legacy inspired him to dream that one day his screenplay could be made into a film and reach as many people as it had with a message of change and hope.

"Big dreams are how change really happens," Black told the audience of film and television writers. "Join me in continuing this fight for civil rights."

But the night truly belonged to "Slumdog," which tells of a young Indian boy who competes for love and money on a TV game show. Together with the WGA's honor, it has now earned top awards from the other major Hollywood guilds and is the clear frontrunner for the best movie Oscar.

"Slumdog" was named best movie by the Producers Guild of America, Briton Danny Boyle was picked best director by the Directors Guild of America, and the movie's actors were judged best ensemble cast by the Screen Actors Guild.

The Oscars, given out by the Academy of Motion Picture Arts and Sciences on February 22, and many of the guild members also belong to the academy making their awards key indicators of winners of Academy Awards, the world's top film honors.

Beaufoy, however, was not on hand to accept his WGA trophy as he was traveling to London for another awards ceremony given by the British Academy of Film and Television Arts (BAFTA).

In other top film awards given yesterday by the WGA, Israeli war film "Waltz with Bashir" was named best documentary.

Major television awards went to "Mad Men," whose writers won for best TV drama, and to "30 Rock," which took home the WGA trophy for best TV comedy.