Arte d'arrangiarsi- the art of making do, of getting by, of adapting to circumstances- with the subtle implication that scruples are not a big part of this. Dangerously close to opportunism.
Mafia- suh-prize, suh-prize!
Pizza- 'nother big fat surprise. I suppose that spaghetti should be included in the category, as it was shockingly not mentioned in the survey.
Italiani brava gente/la mamma. The perception (perhaps somewhat at odds with Italians-as-mafiosi at number two) that Italians are good people, salt of the earth. Tied with the idea that they are mammoni, very if not overly attached to their ma.
Qualunquismo- that they don't really give a damn who governs them, that all politicians are the same anyway and thus the average Italian can't be bothered to get involved. From qualunque (anyone) and the post-War movement of L'Uomo Qualunque (ordinary man).
Gesticulating- is this a stereotype?
Gattopardo- that they believe, with the French, that the more things change the more they stay the same. And that what's more, it should be like this, or at least it has to be. Dangerously close to fatalism. From the famous novel of the same name by Tomasi de Lampedusa.
Weighing in at less than than 5% are tangente (bribe, kickback); mandolin (kinda like it); Pinocchio (like him too); Casanova/Latin lover; vitellone (immature adults, especially male, who won't grow up, from Fellini's film), related to the idea of over-attachment to mamma; dolce vita, their tendency to take life easy (long lunches, plenty of wine, naps, not too much work), also from a Fellini movie; and regional slurs such as terrone for Southerners (from terra, earth, as they were formerly mostly peasants) and polentone for Northerners (from their habit of eating yummy polenta, especially in the past when that's pretty much all they had).
Conspicuous by its absence is Fascist/Mussolini, perhaps relating to another trait sometimes ascribed to Italians- their ability to conveniently forget their history. Of course they have a lot of history to forget.
(In the photo, the great actress Anna Magnani emoting)