Microsoft has launched Internet Explorer 9, the latest version of the firm's web browser offering a slew of new features and performance enhancements.
Unlike arch rivals Firefox and Chrome, IE9 will not run on Windows operating systems older than Vista which means that the next-gen browser does not work on the world's most popular operating system, Windows XP.
Exactly how compatible IE9 is with HTML5 is still somewhat in debate with Firefox developer Mozilla claiming last month that IE9 was still "not a modern browser" due to allegedly spartan support for HTML5 features.
HTML5 also represents a standard battleground with Microsoft ramming a stake in the ground for the H264 video standard, refusing to support Google's 'open' WebM video codec. In this Microsoft stands with fellow H264 patent pool member Apple in giving the open web codec the cold shoulder.
Another contentious issue is WebGL, a 3D description language which is broadly supported by Microsoft's competitors but is a glaring omission from IE9, likely due to Microsoft wishing to preserve the market for the firm's Flash-competitor Silverlight.
The latest incarnation of IE is a welcome addition to the web with ZDNet UK's rather more upbeat Simon Bisson saying that the new browser "put Microsoft back in the game."
Mainstream users are also unlikely to care that much about rival chest-beating about standards support with little web content using these features today.
There's little doubt that IE9 is the strongest browser published by Microsoft yet, however the market in browsers today is vastly more competitive than it was.
Microsoft's market share of web browsers will struggle to regain losses to rivals if only due to the support of only the latest versions of Windows.