Can't say I agree with the substance of this article. A lot of the drawbacks seem to be either preference, something that has been improved already or something

Can't say I agree with the substance of this article. A lot of the drawbacks seem to be either preference, something that has been improved already or something that just required a tad more effort (e.g. I found the testing resources for Flex to be pretty reasonable). All things being equal, is there anything technically compelling to favour Silverlight over Flex?