Internet Explorer’s status as the world’s most widely used web browser will be further challenged in the coming weeks, following the release of two major updates from Firefox and Opera that boast a range of security and reliability improvements as well as a bunch of new features.

First up is Opera 9.5, which today made its public debut claiming to be dramatically faster than its predecessor. Some new and improved features of the browser include Quick Find and Opera Link. The former will be instantly recognizable to any Firefox 3 user as mimics that browser’s “awesome bar” that helps users locate pages in their history by typing a key word onto their address bar. As for the Opera Link feature, it will enable a seamless web experience from device to device by synchronizing bookmarks between any Opera 9.5 desktop browser and Opera Mini whether on a mobile phone, desktop, or even a Wii.

Meanwhile, Mozilla has finally set next Tuesday, June 17, as the official release day for the upgraded Firefox 3 browser, following 34 months of active development and contributions. The team also made available Release Candidate 3, its final release candidate before ship. Windows and Linux users won’t notice anything new in RC3, though, as this update specifically addresses a stability issue in Apple’s OS X.