According to ars technica:
Windows developers have invested a lot of time, effort, and money into the platform. Over the years, they've learned Win32, COM, MFC, ATL, Visual Basic 6, .NET, WinForms, Silverlight, WPF. ...
ZDNet's Adrian Kingsley-Hughes, meanwhile, tries to soothe ruffled feathers by noting that this isn't the first time Microsoft has tried to integrate HTML 5 with Windows; that it's only for touch, not the entire Windows development ecosystem; and by predicting that this is only a short-term solution. He's betting that if touch really takes off, Microsoft will come up with something better.
Recruiting firm CyberCoders named HTML 5 among the hottest skills for 2011. (See related slideshow.) And HTML 5 has been getting even more buzz since TechCrunch reported that Facebook is creating an HTML 5-based platform to work on mobile Safari, a project code named Project Spartan. It's also finally close to releasing an app for iPad. But Liz Gannes at All Things Digital says it's not so much about Facebook taking on Apple, as TechCrunch's MG Siegler suggests, as getting away from having to create apps on all the different platforms and improving Web apps. She notes that Facebook committed earlier this year to an HTML 5 strategy and is working with game developers to make the move.
So on the careers front, yes, HTML 5 looks like a good investment for your time and money. (There's always something else to learn, isn't there?)
Developers can expect to hear more from Microsoft at the BUILD conference in September and at Facebook's annual f8 developer conference.