I/O, the first developer conference hosted by Google, begins today at the Moscone Center in San Francisco, where more than 2,900 developers have already announced their presence.

The event will offer about 100 technical sessions for a large number of developers interested in upgrading their applications for the Web Platform. The sessions will include news about the Google Gears technology, expected to boost browser power, Google Open Social, demos for the Android Application and a highly anticipated announcement about the restrictions-lifting for Google App Engine Also the two new tools for Google App Engine developers will be presented: an image-manipulation API and the memcache.

Vic Gundotra, vice president of engineering for developer products at Google, was quoted by ComputerWorld saying: "All the activity you've seen in the past year is indicative of how serious Google is about developers and our level of commitment. This is the beginning of a very long-term commitment we have."

Google’s hosted computing environment, Google App Engine, was launched in April as a free preview service, available only for the first interested 10,000 developers. After receiving a large number of requests, a waiting list was introduced and an additional 65,000 developers were let in. The service currently cuts off applications when the resource usage reaches a certain point.

The new usage fees for storage and bandwidth will be competitive to Amazon’s S3 as follows:

-     free quota to get started: 500MB storage and enough CPU and bandwidth for about 5 million page views per month

- $  0.10 - $0.12 per CPU core-hour

- $  0.15 - $0.18 per GB-month of storage

- $  0.11 - $0.13 per GB outgoing bandwidth

- $  0.09 - $0.11 per GB incoming bandwidth

Additional storage capacity will be offered for between 15 to 18 cents per month, per gigabyte. Additional CPU processing will be available between 10 and 12 cents per CPU core-hour and finally, additional bandwidth will cost between 11 and 13 cents per outgoing GB and between 9 and 11 cents per incoming GB.

Access to the service has been requested by another 75,000 developers, and Google will present today its plans to offer the App Engine to all interested developers, keeping it free when signing up.

The Web application hosting platform service leaves room for improvement and Google still considers the current version a preview of its efforts. At this point the company is gathering information and feedback in order to resolve all issues concerning its service.

The two new announced tools for the web applications platform will offer a large variety of features, with the image-manipulation API allowing developers to scale, crop and rotate images and the memcache offering its users access to a high-performance caching system.

Unfortunately, no additional languages will be supported.

Another awaited topic involves the release of the new 1.5 Google Web Toolkit version, which is expected to be available later this week. The Java software development framework is designed to develop and debug Web applications, offering important performance and productivity gains, especially by removing the browser compatibility issues.

After all the meetings and sessions will come to an end, an update will surely cover all the aspects unaccounted for in today’s story.