Viewers who feel limited by Hulu's five episode cap for each series will soon be able to pay a monthly fee for unlimited access to an entire back-catalog of TV content. Hulu has steadily increased its following and is now the second most popular destination for online video, albeit a distant second from Google's YouTube dominance. Each Hulu viewer watches an average of nearly 2.5 hours in a month, according to the latest data from Web tracking firm Comscore. So pumping up the amount of available content will only entice these captivated viewers more than they already are. Will people be willing to pay for such a service, though? Netflix offers an all-you-can-eat digital streaming service for similar price tiers (its subscriptions include the standard DVD-by-mail service as well), but the immediacy of the content on Hulu sets it apart. Regardless, Hulu says it will continue to offer up to five full episodes of each TV series for free access. It's only those customers who want to go back into the archive of the series who would need to pay a monthly fee. The premium subscription package will reportedly be called Hulu Plus. "The challenge will be whether Hulu Plus has enough ‘added value' so that consumers perceive that it's worth the price," said Gartner analyst Michael McGuire in an LA Times piece. Hulu will reportedly begin testing its new "Plus" service late next month.