ciccia22: Manuals were valuable source of info back in the day.
I still have some old ones... do you remember Caesar III manual? It was a book!
Now they are not necessary, but it's still something nice to read. Am I the only one who reads them? :(
I used to enjoy reading manuals - often they would give nice tidbits of story to add to the game. I also liked how the old RPG's would give skill and spell information.
Unfortunately manuals were one of the first things to be cut when costs started to rise (at least I hope it was due to costs rising) and we started getting those cheesy 3 page manuals with basic controls and credits :/
Now most games come with in game tutorials (remember, early games didn't really have this convention) - but I have often come across games where the in game tutorials were seriously lacking in detail (or completely missing) and a manual would have been nice. WIth digital distribution it is easier to distribute a manual (just add a PDF file) but I find myself less willing to read a PDF manual because I generally don't want to tab out of a game to read it.