Melbourne has been voted the best overall city in the world numerous times. It certainly isn't because of a large number of sights, photo opportunities nor general tourist interests. But one of the big factors is certainly the multicultural volume of restaurants, the lazy cafes and the quality of places that succeed. I wouldn't pick it as a place to spend a holiday in, but if you live there or simply passing through you can eat well anywhere.
My recommendations of places are not ones that I have been to often (as I always like trying new places or usually cook at home), but they are venues that I can almost guarantee you will enjoy and I do choose them when lazy and indecisive. The latest wave of popular venues incorporate the concept of shared plates and thus community and socialising. It's something that has taken over Melbourne and equally many of the newest and lately popular places in USA and London.
If you're from Melbourne then if nothing else you can see if your tastes are similar to mine:
Favourite Restaurant in Melbourne - Longrain
Favourite Meal of 2011 - Newmarket Hotel (3 course sharing menu)
Favourite Breakfast/Brunch - Three Bags Full, Mitte
Favourite Socialising/Sharing - Longrain, Newmarket Hotel, Izakaya Den, Mamasita
Favourite Fine Dining - Jacques Reymond, Cutler & Co., Ezard
Favourite Chai Latte - Three Bags Full
Favourite Vietnamese - Pho Chu The
Favourite Thai - I Spicy 2 (general), Paladarr Thai Issan (northern), Longrain (modern)
Favourite Malaysian - Laksa King (general), Blue Chillies (modern)
Favourite French - Madame Sousou (general), Jacques Reymond (fine)
Favourite Chinese - Taipan (yum cha), Golden Dragon Palace (yum cha), Pacific Seafood House (Cantonese)
Favourite Japanese - Yokoyama (general), Koko (overall), Shira Nui (sushi), Verge (fusion)
Favourite Tapas - Anada
Favourite Steak - Cutler & Co, old Bistro Guillaume
Places to try - Dandelion, Attica, Cumulus Inc., new Bistro Guillaume, Coda, Golden Fields
This post will be updated as I go along.