I don’t think Apple is going to ignore non-Apple document formats and productivity apps, especially considering, e.g., the fact that Apple was an early Open XML supporter and also had early support for ActiveSync. See Which Apps are Threatened by Apple’s Upgrades? (also in NYTimes.com) for more analysis.
There was no mention of Microsoft Office software like Word and Excel or Adobe Acrobat. If it doesn’t work with those applications, iCloud would have limited utility for many people.
Aaron Levie, chief executive of Box.net, an online storage company, pointed out in a blog post on Monday after the announcement that the shortcoming would be particular problematic for business customers, who often use a variety of file formats.
“The first issue with iCloud is that it will be optimized to work with other Apple products,” he wrote. “The de facto difficulty with Apple (speaking as a customer and amateur pundit) is that they are laser focused on their own ecosystem.”