I came across this white paper titled 'Office SharePoint Server Web Browser Support', it covers the how SharePoint supports level 1 and 2 browsers, but the authors have done extensive testing on the most common features in SharePoint and provided a matrix of what does and doesn't work. They even cover some work around's like using the Telerik RAD editor for SharePoint.
I'm blogging about this as much for my own memory as anything else, you always come across these great resources and can never find them again.