Ask HN: Calling all “foodies” – how effective do you find Yelp?

As an individual who typically eats out on weekends (only) - I've found in a number of cities - NYC, San Francisco, Philly, etc. restaurants having 100s, or 1000s of reviews with 4 or greater stars...leaving the restaurant scratching my head wondering "how the heck was that rated so well"?

I'm wondering how effective you find Yelp's reviews / rating system in your city <x> ?

What DO and DONT you like about it?

Thanks!