I think the scandalous referee favoritism has died down a lot in Serie A since Calciopoli, it is right now close to the level in England and Spain with the big teams (especially during home games) favored over the relegation strugglers. The 06-07 season was different, I'm not much of a conspiracy theorist but there was some real bullshit going on back then almost every round...
Yes that still happens, Samp may be top of the table but are still a mid-table club and Inter in most matches get preferential treatment over mid table clubs. Barca and United have the same shit going on