The explanation given by Hulu on their Stargate Universe page: "The first 3 episodes of the new season will be available the day after their original airdates. Subsequent episodes will become available 30 days after their original airdates."
"For example, a group of military officers launched CompanyCommand.com in the early days of the current Iraq war. At the site, they shared tips and warnings about locations in Iraq, and the site rapidly grew to have thousands of members, Ben-Ari said. The U.S. military threatened to shut the site down because it was on the open Internet, but it eventually moved the site in-house and restricted access via passwords.
""... spam filters block all messages containing the word 'vitamin,' but fail to block messages containing the word 'B12.' If the program never saw 'B12' before, it's just a word without any meaning. But you would know it's a vitamin," Markovitch said. "With our methodology, however, the computer will use its Wikipedia-based knowledge base to infer that 'B12' is strongly associated with the concept of vitamins, and will correctly identify the message as spam," he added.