These are some of the best RSS feeds I've found for keeping up with HTML5. I'm doing jQuery & MVC development as well so you will find the links have a jQuery/MS angle to them.

WhenCanIUse

The oh-so-necessary caniuse.com, in RSS update format: http://feeds.feedburner.com/WhenCanIUse

ScriptJunkie

http://services.social.microsoft.com/feeds/feed/query/tag/scriptjunkieLearn/eq/ns/DiscoveryFeedTool/eq/and
A good HTML, JavaScript, CSS site hosted by MS

Rachel Appel's blog

http://rachelappel.com/rss?containerid=13
HTML5, JavaScript, and MVC links with a general MS angle

Smashing Magazine

http://rss1.smashingmagazine.com/feed/
Really high quality articles with a focus towards the design side of the web development picture

IEBlog

blogs.msdn.com/b/ie/rss.aspx
No surprise - the focus is on IE10, but it is really a great resource for new browser tech.

MisfitGeek

http://feeds.feedburner.com/MisfitGeek
Joe recently switched from MS to Mozilla. New job but he still puts out great Weekly Links summaries.

The Big Web Show

http://feeds.feedburner.com/bigwebshow
A podcast covering web development & design topics

Elijah Manor/Web Dev .NET

I'm cheating on this one a little bit. Elijah is a fantastic JS & web development resource. He has a site at Web Dev .NET, but honestly these days you are better off following him on Google+
...and you can of course sign up to follow the W3C as well, although I don't think there is an HTML5-specific RSS feed. Good luck!