In driving transactions, simplicity matters a lot. And amid eBay’s Innovate Developer Conference 2011 this week, the company alerted the world to the latest way its PayPal division is doing just that online.

PayPal Access, the name of the new feature, is essentially Facebook Connect for consumers shopping online. To put it another way, PayPal Access serves as a consumer’s identity authentication and log-in service for e-commerce sites, and interestingly enough, does not require users to pay via PayPal. The goal of the new service is to reduce friction when consumers checkout online, so everyone buys more things.

The advantage for consumers using PayPal Access is saving them time from the hassles of re-entering info like their shipping addresses and passwords. And with fewer steps and clicks required to complete a transaction on an e-commerce site, PayPal says fewer cases of shopping abandonment will occur. That’s good for the merchant. We suspect it also means more transaction fees for PayPal, too. Though consumers aren’t required to pay with their PayPal accounts, it seems highly likely they’d be more inclined to do so. Becoming a consumer’s commerce identity, which is PayPal Access’s aim, could also mean becoming his online default payment. That’s huge. It also means PayPal would own a lot of data that the retailer would historically own. Because of such, PayPal will have the hurdle of convincing retailers why they should use them, rather than their own registration systems.

PayPal Access is only one initiative of eBay’s new X.commerce open platform, a suite of e-commerce services that wants to redefine commerce’s future.

Separately, PayPal announced a number of new relationships this week, including a partnership with NCR and SI that lets people make PayPal P2P payments from ATMs. PayPal has also announced a partnership with mobile banking technology provider mFoundry.