Using ArcGIS Pro 1.2 to publish a web scene with extruded state polygons. In ArcGIS Pro, they appear correctly and it passes the analysis. Here is how it appears in ArcGIS Pro:
When I load the map in ArcGIS Online the extrusions do not appear to work:
The color symbology is correct but it is rendering them as if this were a 2D surface with y-axis vertices at the state boundaries.