Comcast is launching its own video streaming service this week, the company announced on Tuesday. Dubbed "Xfinity Streampix," the new service appears to address concerns that customers are increasingly attracted to online services such as Netflix, Amazon Video on Demand, and Hulu Plus.

Comcast already offers limited streaming access to current TV shows and other content to cable subscribers via its Xfinity TV service. Xfinity Streampix, on the other hand, will give users access to an expanded library of TV shows and movies. Disney-ABC Television Group, NBCUniversal, Sony Pictures, Warner Bros. Digital Distribution, and Cookie Jar Entertainment have signed on as launch partners for the service, which goes live on Thursday.

Like Xfinity TV, Streampix will be included in certain cable subscription packages. However, it will also be offered as a $4.99 per month add-on for other customers. Unfortunately, Comcast appears to be offering the service only to existing video services subscribers; if you're merely paying Comcast for its high speed Internet service, you won't be able to add Streampix.

Customers will be able to access Streampix content away from home via the Xfinity TV website and iPad app. Comcast said it plans to expand access to consoles like Xbox 360 as well as mobile devices running Android "in the coming year."

Given the fact that a cable box isn't needed to access the content, we see little reason why Comcast isn't offering a version of the service to its Internet-only subscribers. These users still have no other choice but to subscribe to competing services like Netflix, which already have much larger libraries of content to choose from and are already available on more devices.