Adobe Systems on Monday launched out of beta Acrobat.com, a document collaboration service that offers businesses an online alternative to Microsoft Office.

While it's too early to say whether Acrobat.com will make a dent in Microsoft's dominance of the productivity software market, the service is likely to appeal to professionals already using Adobe's creativity software, particularly graphic designers and photographers. Adobe claims that 5 million people have signed up to use the service since its release in beta a year ago.

Adobe is offering two subscription services for the online collaboration environment. The basic service costs $14.99 a month or $149 a year, and includes being able to convert up to 10 documents a month to Adobe's popular PDF format. In addition, subscribers can hold Web meetings of up to five people.

The premium service costs $39 a month or $399 a year, and includes an unlimited number of document conversions to PDF and up to 20 Web meeting participants.

Acrobat.com includes a collaborative word processing application called Buzzword with capabilities to adjust page layout and presentation and to save in multiple formats, such as Microsoft Word, HTLM, XML, and PDF.

Adobe on Monday added a preview release of a collaborative spreadsheet-like application called Tables. In May, the company launched a preview release of an application that enables people to work together on presentations. Previews of applications are available at no additional charge.

Adobe plans to add to Acrobat.com several features over the next 12 months, including shared team workspaces and smartphone access. Adobe also plans to improve the service with more real-time document collaboration tools, a more streamlined interface, social network-style updates about the documents people are working on, and deeper integration with desktop tools, including Adobe products and Microsoft Outlook 2007.

Adobe faces stiff competition in the online document collaboration market, including free versions of services, such as Google Docs. Other competitors are Zoho and TextFlow.

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