Having been around open-air drug markets/projects similar to the ones in the Wire, a lot of the show seemed contrived and unrealistic. I haven't watched past the first season. So I'd say Sopranos.
As far as organized crime dramas go I'd say Boardwalk Empire is the creme de la creme.
id have to go with the wire as well for the simple fact once i got into it i bought season 1 watched the whole shit in a day or 2 ..then copped season 2 and did the same and so on...theres still eps of sopranos i need to watch but i always did like that show too i liked the wire cuz every season was diff but it was still the same gritty shit i also liked how it showed both sides of the law id always catch myself pullin for the bad guys..but the cops where actually some what likeable ..like ole boy(cant remember his name) but he was the white guy who was always getting drunk and having sex with all the female cast memebers...oh and him and bunk was close..bunk was the shit too ..the only other series that really got me super into it like that was the shield that used to come on fx
id also add Band of brothers,the west wing,curb your enthusiasm,6 feet under to me list and not forgetting seinfeld
arrested development is just outta me top 5 or 7...... but its a great show also
afew other series i love would be dexter / boardwalk empire / east bound and down / the sheild / weeds( heard they might come back with another season) speaking of when does dexter or east bound n down start back up (or did they already) ? if anybody knows