There are a number of obvious CSS problems on IE8 in the map/layer page:
-playback tools have no backround
-legend swatches too far left
-legend tree moves around when moused over
-playback controls are barely visible
Not sure of the state of these, but moving off to future to do dedicated IE testing then. In the meantime we'll wait for user feedback.
We currently see around 4% of our traffic from IE8 so we might consider warning them as we do for versions less than 8. Either way, low priority for sure.
Closing as IE8 EOL was April 8, 2014