With Apple's Wednesday-released iOS 6 version of its operating system boasting the inclusion of the company's Passbook digital wallet app, the first set of companies which went in for the launch-day integration with the feature included Major League Baseball (MLB), ticket-reseller StubHub and online movie site Fandango.

The evident reason behind the three companies' almost-instant jump on to the Apple Passbook app - which essentially is a virtual wallet capable of storing electronic tickets, boarding passes and coupons - is that they apparently believe in Passbook's potential of bringing paperless event tickets into the mainstream.

With the MLB officials demonstrating Passbook tickets at AT&T Park on Wednesday night, the new virtual wallet from Apple will be tested by the San Francisco Giants, the New York Mets, Kansas City Royals and Boston Red Sox for some of the few remaining home games in the regular season; with baseball hopeful of rolling out the features to all 30 clubs next year.

Meanwhile, so far as the other two companies to have jumped on to Passbook are concerned, ticket-seller StubHub will initially be testing the Passbook feature at University of Texas and Purdue University football games, with some other venues to be brought on in the near future; while Fandango has added the Passbook option to 2,600 screens across the US, including nearly 100 screens in Bay Area theaters owned by bigwig chains like Cinemark, Century and CineArts.