As things currently stand, MS Office has total control over the word processing / spreadsheet / presentation market. There are a few little minows nibbling at Microsoft’s feet but until now there has not been a compelling argument to switch.
However, the advent of the open source office suites (Open Office being the most well known) is beginning to gather some momentum. And now there is another player entering the market.
NeoOffice is an off-shoot of the OpenOffice effort aimed at moving to a pure Java solution for OS X. While only a prototype at the moment I think it is another demonstration that the productivity suite market is going to fragment over the coming years. Already, I can see little reason for the home user to fork out for Office unless they are already tied in a big way to it.