Browser-compatibility tables and feature detection do provide you useful data -- but then it's up to you to know what to do with that data. For example, you may know that HTML5 Drag and Drop is fully supported on the big four browsers; but does that mean you shouldn't consider any other drag-and-drop solutions (say, jQuery)?
These decisions -- the sort that involve compatibility data but aren't necessarily fully determined by that data -- are exactly the sort of decisions you'd love to discuss with other web developers, especially if those devs have more HTML5 experience than you.
html5please.us now offers just that kind of expert advice. Go there for a simple list of popular/cool HTML5 features, each with a prominent 'use', 'caution', 'use with fallback', 'avoid' tags -- plus explanations and polyfills, where applicable.
The website describes itself:
When Can I Use tells you the browser support story, while Modernizr gives you the power of feature detection. HTML5 Please helps you out with recommendations for polyfills and implementation so you can decide if and how to put each of these features to use.