Mobile Internet user to eclipse wireline users by 2015

It’s going to be a mobile Internet world and we’ll just live in it. That’s the conclusion of IDC, which is forecasting that mobile Internet users will grow by an annual compound rate of 16.6 percent through 2015, when they will pass PC and other wireline Internet users.

That’s not entirely surprising if you’ve been following along. Mary Meeker, the former Morgan Stanley Internet analyst and now Kleiner Perkins VC, forecast last year that the cross-over point would come around 2014. She said at the time that we were in the midst of a fifth computing cycle, following the mainframe computing eras of the 1950s and 60s, the mini-computers of the 1970s, the PCs of the 1980s, the desktop Internet era of the 1990s and now the mobile Internet age. Earlier this year, IDC noted that smartphone shipments in the fourth quarter last year topped 100 million units, pushing past PC sales.

IDC said the total number of Internet user will grow from 2 billion in 2010 to 2.7 billion in 2015, with 40 percent of the world’s population online. But as Internet penetration picks up, it will happen more on mobile devices than traditional PCs, something Apple(s aapl) founder Steve Jobs noted in dubbing this the post-PC era.  IDC said that as tablet use in particular picks up, it expects PC Internet usage to stagnate and then slowly decline.

As IDC notes, this shift will make the world a different place. For one thing, mobile network owners will need to get ready for this explosion in mobile data traffic, which is expected to increase 26-fold between 2010 and 2015. Content owners need to think about what they’re doing to optimize for mobile. And retail and commerce companies need to take note of how users are accessing the Internet on the fly, which can provide both opportunities and challenges to online and physical retailers. Advertising and marketing is also being transformed by mobile as brands, and advertisers are starting to look at how to best reach consumers with messages that can be tailored to their preferences, context and location.

It’s a brave new world, and the companies that embrace it will take advantage of the coming opportunities that emerge as mobile devices becomes the dominant way we access the Internet.

Image courtesy of Flickr user watch4u.