In Milan Italian E is closed in when a syllable ends with a vowel: as in bene (be-ne), and it's open when a syllable ends in a consonant: dormendo (dor-men-do). Final e in monossylables is open: tre (thus ventitre`), che` (thus perche`). So, Milan Italian DOES have 7 vowel system, but its redistribution is not based on Standard Italian System (Florence-Rome-based) but on the system of Lombard languages (open/closed is syllable related, whether syllable is open or closed).
In standard Italian it's: bEne (open stressed vowel), dormEndo (open stressed vowel), ventitre´ (closed final stressed E, and therefore acute accent in writing, not a gravis), perche´ (closed final E and not open, and therefore accute accent over e, not a gravis).
Accents and dialects of Central Italy (Tuscany with Florence, Marche, Lazio with Rome, city of Aquila) have the same distribution of open (E, O) and closed (e,o) as standard Italian (which is based on Tuscan dialect), and people there use the same pronunciation as indicated in dictionaries...All tv people working in dubbing of foreign programs into Italian need to use this pronunciation (and not Milan pronunciation, described earlier, with 7vowels, but wrongly distributed, or Turin or Southern (which pronounce all vowel open)...If you listen to the singers from Rome or Tuscany (Eros, Giorgia, Jessica Morlacchi, Tiziano Ferro, Ambra Angiolini, Syria, Giana Nannini, Zero Assoluto, Marco Masini) you can get this perfect, clear pronunciation...
Laura Pausini has 5-vowel system, and people all over the Italy can tell ''accento romagnolo'' (accent from Romagna) in her speech or songs. I don't recommend to copy this accented accent. It's just like Southern US or Scotch English, marked and not neutral)...
there is a bit of a conflict in italy since you have
1. roman tv stations (based in rome) which use the standard italian and
2. private tv stations (from milan) which use italian language, but pronounced with lombard pronunciation (open vowels are used instead of closed, closed vowels are used instead of open, double consonants are not always doubled, GN and GL(I) are simplified, instead of being pronounced as double gngn, glgli (this is the standard pronunciation)).
some clips with standard pronunciation:
Jessica Morlacchi - Un bacio senza fine
http://youtube.com/watch?v=e7EKR7xGl14
Marco Masini & Jessica Morlacchi - Nel Mondo dei Sogni
http://youtube.com/watch?v=hrEv0DwznlA
Zero Assoluto - Semplicemente
http://youtube.com/watch?v=4cuqcMss7hw