I'm working on a holding page at the moment that makes use of css3 keyframes. For browsers like chrome I'm using -webkit- in the css but what about IE9? Do I need to use <!--[if IE9]> with a .js alternative to the css3? If I do go with the .js am I better off just ditching keyframes all together? Or, for the sake of 4-6 weeks till the site goes live can I just ignore IE9 users?