There’s HTML5 and then there’s HTML5. As the recent dust up between Opera and Apple illustrates, various browsers claiming HTML5 support are more and less compatible with the emerging standard. A new benchmark lays this out clearly with Apple’s trendsetting WebKit-based browser earning top marks.

Now, The HTML5 Test grades the compatibility claims of Apple, Google, Opera, Mozilla and Microsoft’s HTML5, assigning specific scores on a 300-point scale:

• Apple Safari 5.0: 208
• Google Chrome 5.03: 197
• Mozilla Firefox 4.0b1: 189
• Opera 10.6: 159
• Mozilla Firefox 3.66: 139
• Microsoft IE8: 27
• Microsoft IE7: 12

Clearly, none of the currently available HTML5-ready browsers is yet good enough, which I would estimate as a score of 270 (90 percent) or better, though great progress has been made.

Still, HTML5 isn’t a fully ratified specification and The HTML5 Test benchmarks against the draft specification. Safari ranks number one, and Opera and Internet Explorer not so much.

Insert foot here…

That said, when Apple published its HTML5 Showcase last month, featuring the video, typography, gallery, transition and VR features currently available in the HTML5 draft spec, Opera Soft was quick to disparage the demos as being Safari specific and an Apple perversion of the nascent standard. Needless to say, Opera couldn’t display much of what’s there.

Now, we know why Opera can’t handle those demos…

What’s your take?