In its ongoing effort to attract corporate customers, Google took the beta tag off Google Apps Tuesday, hoping business users will now see the software as solid enough to use.

One component, Gmail, has been in beta for over five years, wrote Google director of product management Matthew Glotzbach in Google's blog, although he noted that the Google App suite of applications -- which include Calendar, Docs and Talk -- has always had a service-level agreement and 24-hour, 7-day-a-week support.

"We've come to appreciate that the beta tag just doesn't fit for large enterprises that aren't keen to run their business on software that sounds like it's still in the trial phase," Glotzbach said. "So we've focused our efforts on reaching our high bar for taking products out of beta, and all the applications in the Apps suite have now met that mark."

Glotzbach didn't specify what that mark might be, although Google did introduce new features and services that could make the Apps more appealing to corporate customers and easier for administrators to handle.

These include e-mail delegation, which allows IT staff to screen and send e-mail on behalf of others; e-mail retention, which is critical for companies that need to comply with industry regulations or defend or prosecute lawsuits; live replication of corporate data to other locations for disaster recovery; and "special handling" of corporate data in Google's data centers.

Pricing is not expected to change.

Google claims that 1.75 million companies run Google Apps, although many of those are small and medium businesses.

The market for corporate productivity software is still dominated by Microsoft Exchange and IBM's Lotus Notes, according to a report last year from Forrester Research, which said that other vendors, including Google, lack the resources to build and integrate an entire platform of software for corporations.

A group of academics and computer scientists has also questioned the security of Google Apps. Last month 37 of them issued an open letter to Google CEO Eric Schmidt detailing several security problems with the Apps and asking that Google enable industry standard transport encryption technology to prevent snooping and data theft (HTTPS).

Google is considering that request and responded to the group here.

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