It's still unclear what exactly that means, but it most likely means that Amazon.com will produce episodes that will be streamed via its Amazon Instant Video service. It remains to be seen if those segments will be made part of the Prime Instant Video service, which is a subset of Amazon Instant Video.
Amazon Prime members can watch anything in the Prime Instant Video catalog, but not everything in Amazon.com's Instant Video catalog makes it there.
Past reports suggested that "Zombieland" will be streamed in 30-minute episodes, and leaked casting documents suggest that the series will center around the same characters you might remember from the horror comedy film. Naturally, we wouldn't expect the actors to reprise their roles, except perhaps in a cameo.
Prior reports had "Zombieland" hitting on the CBS network, but really, if it will be as bloody as the film or even as bloody as "The Walking Dead," it's not going to be on a broadcast network. We wouldn't have expected it to reach anything less than a cable network.
Amazon.com's Instant Video service hasn't taken much of a chunk out of Netflix' market share, and if the company wants to really make hay, it's going to have to continue with more original programming.
Netflix has a huge year of original programming set up, with the aforementioned "Arrested Development" coming in May, the David Fincher / Kevin Spacey political drama "House of Cards" coming in just a few weeks, and horror maven Eli Roth’s "Hemlock Grove" coming in April.