Get a hotmail account, so you can have email, contact, MSN, calendar, SkyDrive photo, SkyDrive office, xbl achievement all integrated together. Also remember to link FB account for calendar and photo integration. If you link fb account, you can use fb avatars for your friend. If you enable fb message, you can message fb without extra app, problem with it is your hotmail contact and calender will be filled with fb junk friends, hopefully they fix that.
It is save to use, if you compare that to suspicious Androids.
voice command to open games (iPhone cannot do that), voice search, music voice search, vision search.