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Twitter is under pressure to demonstrate more monetization options, and its recently released "Buy Now" button is an obvious step to test the channel's ability to drive affiliate or enhanced ad format revenues. In the current testing incarnation, the Buy Now button simply routes users through to the merchant's website checkout page, but in the future it's possible to see deeper integration between the button and the destination site to enable one-click purchases. However, there's plenty of room for doubt as to the immediate effectiveness of Twitter (and most other social channels) as a channel to drive sales.