I, as most other devs had to struggle a lot with IE in the past and probably will have in the future but what they did is either really silly or a marketing stunt.

IE9 and IE10 probably dont have a high market share at the moment but they will have, so whats the problem in adding prefixes. As you said they also "forgot" opera which forces them to add the -webkit prefix.

And for testing IE simple use https://github.com/xdissent/ievms - i dont see any problem here - nobody compla