I've recently converted a file from WGS84 to AK State Plane 5 NAD 1983 and noticed in the attribute table that the coordinates did not update. I know there is a way to update them so they reflect the new coordinate system but I can't seem to figure out how.
The update of the coordinates only happens dynamically to a featureclass stored in a geodatabase. If the features are stored in a shapefile, then yes, you will need to recalculate for them.
Create a new integer field and when you open the attribute table, right click the fields header and go to Calculate Geometry, from there you are given several options for getting the current coordinates.