There’s a company called Webalo that you might want to look at (http://www.webalo.com) because it manages to work on any mobile OS (though they don’t support the iPhone at the moment) and automatically adapts enterprise tasks and content to each smartphone’s UI. Their approach is very different than traditional app dev. In fact, it requires no SDK or coding.

So, yes, wordprocessing and the creation of spreadsheets aren’t ever likely to migrate from the enterprise to a smartphone, but connecting to those documents (and to just the information that each user needs, instead of to the entire spreadsheet or database, for instance) is already easy to do.