The Michelin tire company launched its first guide book in 1900 to encourage road tripping, and started anonymously reviewing restaurants by means of a three-star system in 1926. It now has guide books in cities and countries around the world, mostly outside the United States. The reason Michelin stars are so coveted is that most restaurants receive no stars at all. Here's an explanation of how Michelin stars are awarded.
- Praise: Michelin is highly authoritative. Its reviewers are anonymous.
- Criticism: The ratings are French-biased and snobby. It's geographically limited.
Yelp aggregates millions of real people's opinions about U.S. restaurants. The process: Go to a restaurant, create a profile on Yelp's site, share your opinion. Here's a good primer on how Yelp works.
- Praise: Yelp is based on the opinions of real people -- who can talk to one another and respond to reviews. Restaurant owners can also respond. Also, since you can see what a particular reviewer thought of a certain restaurant, you can decide whether you're simpatico with that reviewer's tastes.
- Criticism: Yelp has been accused of manipulating reviews -- Yelp denies this. Restaurants also may manipulate reviews.
Zagat guides have been around since 1979, aggregating millions of diner's opinions in destinations worldwide. Real people fill out questionnaires about restaurants that they've experienced, and score food, décor, service and cost, and add their comments. The scores are averaged on a 1-30 scale and editors select pithy comments.
- Praise: You're getting real people's opinions, but not unfiltered and raw.
- Criticism: Since the reviews are aggregated, you can't evaluate whether you'd otherwise agree with the reviewer. Zagat has been accused of "grade inflation", which the company denies.
Mobil awards its stars on the basis of site inspections. Mobil works on a five-star system, but every restaurant that receives any star rating is recommended. Restaurants that might qualify for the top ratings receive extra (and incognito) evaluation. Mobil evaluates food, but also service, atmosphere, table settings and a host of other details. A thorough explanation of Mobil's evaluation criteria here (PDF).
- Praise: Detailed definitions lets you know what the star ratings really mean.
- Criticism: The check-list approach includes things foodies don't really care much about, like the state of the parking lot.
AAA, the folks that provide road-side assistance, also review restaurants, awarding one to five diamonds. Restaurants apply to be evaluated, and if they're accepted (thus becoming AAA approved), one of the organizations full-time reviewers pays an unannounced visit to award the diamonds, from basic good food to fine dining. Here's a detailed explanation of AAA's diamond system.
- Praise: There's no snob factor - basic restaurants aren't excluded.
- Criticism: Restaurants pay a fee to be considered by AAA. Like Mobil, the check-list approach isn't a foodie-centric approach.