Ade told you about some new Missions (1) that were just released to some players. There is a thread on the Zynga Forum Boards titled New Level 100+ Missions which now has a moderator response. Cerulean Master, Super Moderator, lets us know that new Missions are slowly rolling out and will be available to more players next week.
Mafia Wars Wiki Missions Page to see all of the City and Contract Missions currently available. I believe there are around 60 individual Missions if you don't group ones with multiple parts.