Microsoft's Internet Explorer development team acknowledged Monday that it was a mistake not to build tabs into IE earlier.

But the team's not rushing into updating: the tab feature in the next version of the popular browser will on the "basic" side.

"The Tabbed browsing experience in the upcoming IE7 beta is pretty basic," wrote Dean Hachamovitch, IE's product manager, in a post to the team's blog. "Expect additional end-user functionality to come in after the beta," he went on.

IE 7, which Microsoft has said will go into beta this summer and release significantly before Longhorn, with which it was once tied, is a reaction to the growth of Mozilla's Firefox, analysts have said. Firefox, as well as other alternate browsers, such as Opera Software's Opera, already offer tabs to view multiple Web sites within a single window.

"Some people have asked why we didn't put tabs in IE sooner," Hachamovitch wrote. "Initially, we had some concerns around complexity and consistencywill it confuse users more than it benefits them? Is it confusing if IE has tabs, but other core parts of the Windows experience, like Windows Media Player or the shell, don't have?"

Taking the side of caution was a mistake, Hachamovitch admitted. "I think we made the wrong decision here initially, and we're making the right one now."

In other browser market news on Friday, IBM became the latest company to embrace Mozilla's Firefox browser, making it available to 300,000 employees.