It would appear that all of the export names for the vertex data commands have been changed between 7.4 and 7.5 to reflect their accurate "VertexData" name.
This is not a bug per se but it may have the unfortunate side effect of breaking some plugins. I know that DarkClouds, for example, no longer updates its gradient after updating to 7.5. This might be an unrelated issue but there's no way of really telling what might have been affected.
Commands which I know have had their export names changed include:
ADD MESH TO VERTEXDATA
DELETE MESH FROM VERTEXDATA
GET VERTEXDATA DIFFUSE
GET VERTEXDATA INDEX COUNT
GET VERTEXDATA NORMALS X
GET VERTEXDATA NORMALS Y
GET VERTEXDATA NORMALS Z
GET VERTEXDATA POSITION X
GET VERTEXDATA POSITION Y
GET VERTEXDATA POSITION Z
GET VERTEXDATA U
GET VERTEXDATA V
GET VERTEXDATA VERTEX COUNT
LOCK VERTEXDATA FOR LIMB
LOCK VERTEXDATA FOR MESH
SET INDEXDATA
SET VERTEXDATA DIFFUSE
SET VERTEXDATA NORMALS
SET VERTEXDATA POSITION
SET VERTEXDATA UV
UNLOCK VERTEXDATA
There may be more functions than this that I'm unaware of.