I tried the same thing today.
Ashley: system expressions Version and Description would indeed be a nice touch (just a get, not a set).
For now I resolved to make a global variable "PublicVersion" since anyway I don't export as often as I update my sources' version number. So it should be ok as long as I remember to increment this var each export I do <img src="smileys/smiley17.gif" border="0" align="middle" />