How do I find out when I can safely drop vendor prefixes for a CSS3 property?

Question

I was testing some CSS3 stuff and I discovered that some properties like border-radius don't need the vendor prefix anymore (at least on recent up to date browsers).

My next website will only target recent browsers like IE9/Chrome 15+/FF8+, so I was wondering:

Is there a list of the current CSS3 properties where I can see which of them I can safely drop vendor prefixes for?

Note: I'm not interested in JS hacks that automatically insert prefixed properties.

Answer 1

When can I use... contains browser support tables with convenient indicators of which versions of which browsers require the vendor-prefixed versions of various CSS3 features, as well as features in other standards like HTML5, its new JavaScript APIs, SVG, etc. That should be the first place you stop at.

The site is updated regularly (for now, at least) as new versions of browsers are released and the drafts of the relevant CSS3 modules are updated.

Answer 2

http://html5please.us/ Offers a similar service but they also provide advice on fallbacks for CSS3 properties where appropriate. I find both sites useful.