Galactica ending with season 4
Los Angeles Times: Show Tracker: What you're watching

Sad but true: "Battlestar Galactica" will end its run next year after its fourth and final season.
After weeks of speculation, the end is in fact near. According to a high level source at Sci Fi Channel parent company NBC Universal, the show will dock after its next 22-episode season, slated to kick off in early 2008.
Sources say the decision came down from executive producers Ronald D. Moore and David Eick, who are said to feel creatively like this upcoming arc will be its last.
Rumors began circulating this month when two "Battlestar Galactica" stars, Edward James Olmos and Katee Sackhoff, referred to the next season as the show's swan song while attending the annual Saturn Awards.