What happened to it
Little Italy was once a large, densely Italian-American neighborhood covering much of what's now considered Nolita and parts of SoHo. Successive waves of change — the expansion of Chinatown from the south, rising rents, and the gradual dispersal of Italian-American families to Brooklyn, Staten Island, and the suburbs from the mid-20th century onward — have reduced it to essentially one street: Mulberry Street between Canal and Broome.
What's actually there now
Mulberry Street retains a strip of Italian restaurants, cafés, and a few long-running specialty shops, largely operating for the tourist trade at this point rather than a residential Italian-American community that no longer lives there in meaningful numbers. The San Gennaro Feast, an eleven-day street festival each September, is the neighborhood's biggest remaining institution — genuinely lively, historic (running since 1926), and worth timing a visit around if you're interested.
The honest comparison
For food specifically, Arthur Avenue in the Bronx is the more authentic and better-value Italian food destination — a real market, real bakeries, and a clientele that includes actual Italian-American families rather than exclusively visitors. Little Italy is worth a short walk if you're already in the area (it borders Chinatown and Nolita directly), but isn't worth a dedicated trip on food merits alone.
Getting there
The 6, N, Q, R, W, J, and Z trains all reach the area via Canal Street or Spring Street stations. Little Italy borders Chinatown to the south and Nolita/SoHo to the north — easy to combine into one downtown walk.