What kind of downtime is acceptable to you for the applications that you use? Do you rely on an application always being available? What would you do if you are inbetween two meetings and turn on your laptop to see what meeting to attend to next, but the calendar is not accessible or does not load all information?
Are the applications you use integrated with each other in the way you need them to be in order to be productive? Can you easily move your content between different applications, as you can open and manipulate an RTF document with different desktop applications? Or can you use the contact information in your contacts application in all other applications where you need to access them?
Can you find all the applications that you need from one provider, or are you using applications from different providers, each with a different authentication solution? Would it be acceptable if you would to log on to each of your desktop applications with a different new combination of user name and password? What happened to single sign-on?
Is your content in safe hands? Are you confident that it will not suddently disappear without being possible to restore, or that it will not fall into the wrong hands? How do you back it up in a simple way?
How mobile can you be with your web 2.0 apps? Is your content accessible when you are on the move, from mobile devices? How do you syncronize your cell phone calendar with your web 2.0 calendar application in a simple way?