Fittingly, on the same day last week both Facebook and Twitter announced forays into the e-commerce arena, which looks to be the next battleground in the world of social media.

Facebook revealed that it was currently testing a “Buy” button on ads and Page posts that allows users to purchase products directly from businesses, without ever leaving Facebook. Just hours later, Twitter disclosed it had purchased Cardspring, a mobile payments infrastructure company that enables merchants to offer deals to consumers that can be loaded onto to their credit cards.

“We have seen evidence that Twitter wants to do the same thing as Facebook — participate in that transaction,” Brian Blau, a research director with Gartner, told Mashable. “They’re just getting started with collecting peoples’ credit cards; Facebook has been there for awhile.”

Analysts agree that the end-goal for both companies is to leverage commerce as a way to increase engagement among users by giving them another reason to stay within the social network, in addition to any boosted revenue generated from advertisers.

While the utility of a Facebook “buy” button is fairly obvious, the benefits that a company like Cardspring could provide Twitter do not require much of a leap either. Picture this: After spotting a retailer’s tweet promoting a product or a particular deal, users would simply click a button or send a reply to add the discount to a stored credit card, all without leaving Twitter.

“We see the intersection of payments and digital media as an opportunity to revolutionize how consumers use credit and debit cards, while helping retailers to connect and communicate with their offline shoppers,” Cardspring said in a statement.

In the near future, the entire web experience could be delivered through a social network. Facebook, for example, already offers chat, email, and even a audio ID service.