I've been reading Chowhound's boards for a couple of years now and have to say am a little disappointed with the constant recycling of the same restaurants. Some of them are good, others great, but a lot are pretty average.
I've lived in China for four years now and have eaten my way across the country (and its cuisines!). For what it's worth, my favourite food cities are Beijing (bureaucrats and diplomats know how to eat well) and Qingdao (best produce in China certainly helps, as does the massive Japanese and Korean community plus a citizenry dedicated to having a good time).
I've eaten high, I've eaten low, and I've a lot in-between, so I feel qualified to make judgments about restaurants here in Shanghai.
Here are some of my favourites:
Asman - brilliant Xinjiang food on Fuxing Lu, near Xiangyang Lu. The staff only occasionally break into singing and dancing and only ever near closing time, giving you a chance to eat in relative peace. It's on the Southeast corner, up the stairs - look for a small reception area next to a giant BBQ. Aside from the fish (I can't see the wisdom in trusting a desert-people with fish), it's all delicious. English and photo menu.
Dongbei Four Seasons Dumpling King - hearty and cheap Dongbei food on Xikang Lu, near Wuding Lu. There are other locations too. Try the julienned-stomach salad, the di san xian, the gu lao rou, the xiang su ji, again, this is a place where it's hard to go wrong. The dumplings are also excellent. They've just re-written the menu with good translations and clear pictures.
Cha's - old-school Hong Kong cafe food on Sinan Lu, near Huaihai Lu. I'm sure it's probably been written up elsewhere on the website. The occasional hygiene issue doesn't distract from the absurdly tasty food. Be prepared to wait a LONG time. Go with the classic dishes - you'll recognise them as soon as you see the menu. Full English menu.
Legend Taste - Yunnan food on Kangding Lu, near Wuning Lu. I think I saw it referenced once here. Great Yunnan food (a couple of let-down dishes on the menu though!) with the best feature being that it's at least the half the price of most other Yunnan restaurants in town (such as Lost Heaven etc). English and Photo menu.
Lanzhou La Mian - part of a franchised-chain of Muslim noodle restaurants, the one on Wuyuan Lu, between Yongfu Lu and Wulumuqi Lu is the best. Ask them to set up a table for you outside and get the fried egg and coriander on top. Picture menu only.
Franck - French bistro on Wukang Lu, near Hunan Lu. The bad service reputation (which I think unfair) doesn't diminish from what is one of the best French bistros in Asia. Given a choice between this and any other restaurant in Shanghai I know few people who would go elsewhere. French-only menu.
Toriyasu - Yakitori restaurant on Huichuan Lu, near Changning Lu. Great food, atrocious service. Probably too expensive for what it is and out-of-the-way, but worth it for the occasional splurge. Sit at the bar area. No English or photo menu.
Masala Art - Indian restaurant on Dagu Lu, near Chengdu Lu. Excellent service and great food make this the restaurant of choice for us Shanghailanders. Full English menu.
Pasha - modern Istanbul bistro on Nanchang Lu, near Maoming Lu. Good food, cheap wine, nice service, and shishas make this a lovely place to spend an evening. It's a good middle-priced date restaurant. Full English menu.