Are you sure you are not a MSFT shill or anything? This almost reads like MSFT is paying you to write this post.
Yes IE is BETTER with html5 support and performance and general overall standard support for css/html and js performance. As it has been the case incrementally since IE7. But to point out benchmark specifically designed by IE to exploit elements of html5 (and other standard support) that IE is better at is just ludicrous.
Obviously MSFT browser does better in benchmark made by MSFT.
Kraken Benchmark is JS benchmark developed by mozilla and guess which browser performs best in this one? Of course FF!
V8 js Benchmark developed by Chrome and Chrome performs best in this benchmark.
There are lies, damn lies and benchmarks.
Real world usage is all that counts.
The whole html5 Valhalla is of-course a sick marketing joke because html5 is still not a standard and very much subject to massive changes until it reaches "candidate recommendation stage" which is at the end of 2014. Most serious web developer wouldn't touch html5 with a long stick until it reaches close to standardization. Sure its cool and new and shiny but its not ready yet for wide adoption for until another year or two.
Here are some third party (hopefully neutral) benchmark and review of IE10's performance compare to others:
As for developer tool in IE10, this is almost exactly the same one as in IE9. Webkit (powers chrome and safari) is virtually the industry standard in developer tools feature and performance, Opera's dragonfly is a close second but very few people actually uses Opera. Firefox firebug is of course the industry darling for the longest time but might be getting out of favor recently. The FF16 has an interesting take on their new built-in developer tool but I personally don't like it very much.
IE developer tools is pretty much the lowest common denominator
in developer tools out there. The IE10 developer tools feature you mentioned has been around on webkit and others for at least 4-5 years now.
If I sound butt-hurt about anyone praising IE its probably because I am. Being a web-developer for 10+ years its very hard to like IE at all and easy to look through their lies and deception.
The best thing that ever happened to IE is Chrome. Once Chrome entered the scene, IE started getting their sh*t together.