4, as of 6-30-09.
As high as you can practically go
As of now, there is no known limit.
Unlimited, or as long as YOU can go i guess you can say.
you will need approximately 368 Blackmail Photos to complete the Boss job tier.
In Mafia Wars, the weapons depot has a total of 10 levels. Each level unlocks new weapons and upgrades that can enhance your gameplay. Players need to accumulate resources and complete tasks to advance through these levels.
you need about 380+ illegal transactions. (this may be how many one needs total for all of the jobs requiring "illegal transaction records," but is an incorrect answer for how many are needed for just the three boss tiers - boss/skilled boss/master boss.)
untraceable cellphones are not required for the Boss job tier in New York but it is needed in the underboss tier and El Cacique tier in Cuba.
You can only have a maximum of 501 and many people have that.
There are three different levels on each job. For each level you are awarded a tittle. Level 1 - Street Thug, Capo, Boss, etc... Level 2 - You become a "Skilled" Street Thug, Capo, Boss, etc... Level 3 - You become a "Master" Street Thug, Capo, Boss, etc... Also once you complete level 3 you earn a special prize that is added to your loot section
joining a clan or family, or by posting to one of the many different sites that are mafia wars add sites. Depending on where you play, you can just type mafia wars into the search site, and many different things should come up.
so far there is no limit on how many family you can have on your mafia family but you can only take 500 mafia families to attack.