I had a good time reading the manual while the game was installing and it led me to believe that the game was going to be something pretty damn good. The manual was quite informative at the time, even though the game quite clearly didn't work, and appreciably reflected what players can expect in the game and helped them to understand key game concepts. The game has since changed in serious ways and is going to keep changing.
Unfortunately, it seems more than likely that Stardock is going to keep printing the same manual and/or not include addendums in boxes that are hitting retail. Even if Stardock does ship new manuals and/or addendums, players that have been following development of Elemental at a distance aren't likely to have a nice, clean, clear manual or addendum to their manual to help them keep track of new game mechanics. A solution to the problem is rather simple and is something that we've seen with the new Civilisation V game: a downloadable .pdf that functions as the game manual.
Granted, Civ V's manual is pretty bad in that it contains several serious misprints and complete omissions of referenced game mechanics (unit maintenance) but it is easily accessible. Stardock would be operating at too much of a loss to print these things and they could also play the game of hopping on the green bandwagon if they used a .pdf file downloaded via Impulse. It seems to me that this is a simple solution and wouldn't take too much effort on Stardock's part.
(Note: 'Check the wiki,' is not an appropriate response.)