Apple is believed to preparing Charts 1.0, a spreadsheet application that will round out their iWork '07 suite. I prefer the name that Apple trademarked in June 2005 ("Numbers"), so that's still an option. The new spreadsheet program will be make iWork '07 an honest-to-goodness challenger to Microsoft MBU's Office for Mac.
Pages 3 is reported to get two modes, Word Processing and Layout, to separate the discrete editing functions (lookout Adobe InDesign). Apple will most likely integrate Charts into Keynote 4 in addition to more cinematic transitions, Apple-created themes and more high-quality clip art.
A really nice bonus would be for Apple to add a database application to the iWork suite, it's the only application that's missing. They can either license or acquire Filemaker (which just turned Universal) or build a Microsoft Access-equivalent tool for Mac OS X.
What about a professional version of Mail? Email is arguably the most used single application on anyone's computer - Apple could improve it. Or Apple could take it another step further by rolling-up Address Book, iCal and Mail into one killer groupware app. An elegant Apple groupware application could be a real Outlook killer. iPlan anyone?
Do you use Pages and Keynote now? (Sure you do.) What percentage of time versus Word and PowerPoint?
What do you want to see in iWork '07?