A dark trend runs through this year's Web 2.0 tech summit

[Commentary] Normally a sunny celebration about the future of the Web, one of the largest annual gatherings of the Internet elite took on a darker and more pessimistic tone this week. The fear that ran through the seventh annual Web 2.0 Summit is that the days when the Internet was a playground for startups with unlimited potential are disappearing.

Instead, we are moving into an era dominated by a handful of new Internet titans more interested in fighting each other for power and influence than in delighting users with new innovations. The names of the culprits are familiar, and include Apple, Google, Facebook and Amazon.com. Each has assumed a dominant position in their respective markets -- mobile, search, social networking, e-commerce -- and are focused on how to defend their turf while infiltrating their rivals' territory. We, the consumers, are caught in the crossfire. We're likely to see fewer new products (like Twitter) and more services aimed mainly at locking us into the new Internet titans (I'd count Facebook's new message service in this category). By building up their walls, they keep us inside longer, allowing them to amass an arsenal of data about our behavior. And they have become so indispensable it becomes almost impossible for us to contemplate leaving them.