The FeatureTable dijit in the Javascript API currently has no method for refreshing its data source. This is needed if the data layer it links to has changed, either by editing, or the application of a definition expression. I think the only way to do this currently is to destory the dijit, and re-create it.
In my current application, I am showing various locations of damage caused by natural disasters. Each location has a date associated with that disaster event. My interface has a combo box where the user can select a specific disaster event date and then the map is filtered to only show these locations. This filtering (by way of a definition expression on the featureLayer) breaks the FeatureTable. A quick call to a refresh method would fix this easily for me.