By Jim O'Neill, Research Analyst

Over the course of the post several months, Amazon.com has become increasingly aggressive in acquiring exclusive content for its Prime Instant Video Service.

Amazon today announced a new deal with CBS that is likely to spread a minor shudder of angst amid its biggest competitors, Netflix and Hulu.

The two have struck an exclusive content licensing deal that gives Amazon rights to the new CBS television series “Under the Dome,” establishing an in-season, online subscription-video-on-demand (SVOD) window for the show on Amazon’s Prime Instant Video service. The serialized drama--from Steven Spielberg’s Amblin Television—premieres on CBS June 24.

Amazon Prime members—who pay about $80 per year for unlimited two-day shipping on eligible items, and get the Instant Video service as a free value add--will be able to stream the series four days after its initial broadcast on CBS, to devices Kindle Fire HD, iPad, iPhone, iPod touch, Roku, Xbox 360, PlayStation 3 and the Wii U gaming console. Episodes also will be available to buy.

“With this innovative agreement, we’re giving fans more options to watch and stay current with this serialized series, and doing so in a way that protects the Television Network’s C3 advertising window,” said Scott Koondel, chief corporate content licensing officer at CBS.

For CBS, it’s another opportunity to take advantage of a digital market that President and CEO Les Moonves once was leery of. For Amazon, it’s a chance to show just how serious it’s becoming about OTT.

Amazon’s Prime Instant Video launched well after Netflix and Hulu, and, with a significantly smaller library. The company, in recent months, has shown that it’s becoming a force to be reckoned with.