From what I understood, you will need this application if you want to be able to sync your phone with your computer or ipod etc. I'm still not 100% on it but that's what everyone keeps telling me, just, "You gotta have it".
Mobileme is an app which will automatically push all your new mails, contacts to your iphone. Your pc and the phone will stay in perfect sync, you need not dock it instead you are using this app.
And it is completely the users wish to either use this app or to use a new one.
