Microsoft maintains that it probably will not need to go to a second release candidate and the feeling is that RC1 is almost the finished product.

The major differences between IE7 RC1 and the previous beta releases are in improved performance and the ability to install it automatically without the need to manually uninstall previous versions. There are also additional language options.

Microsoft watcher Paul Thurrott says of IE7 RC1 on his Super Site for Windows blog: "It's a required update for any users who installed IE 7 Beta 3 or earlier. As for IE 6 users, I think it's both safe and prudent to migrate to IE 7 now."

However, Thurrott also says: "I don't think there's enough there to sway Firefox users quite yet."

Speaking of Firefox, which is now estimated to have more than 15% market share, Mozilla is due to release FireFox 2.0 Beta 2 on August 30, slipping seven days behind its original August 23 schedule. Firefox 2.0 release candidates are due in September with final release due on October 24. With the current slippage of Beta 2, it is not clear whether Mozilla will hold to the October 24 deadline.

While it is unlikely that Firefox will suffer significant defections to IE7 as a result of being a few weeks late to market with its new release, winning customers from the much improved IE7 will be a much tougher proposition than from IE6.

The world is waiting to see Firefox 2.0 can maintain the edge Mozilla has established in the browser war. {moscomment}