789 and 790 usd in Bitstamp and bitfinex respectively but the interesting point is the price in localbitcoin 849 usd in preev

Localbitcoins is always above the exchanges with price and it's logical. It requires people to meet in person and that takes more effort than a couple clicks and much more time.
If you want to know "standard" bitcoin price. Then you can't use:
1. Local exchanges - they sell more expensive BTC (due to limited volume and increased demand) - just look at Indian and African exchanges.
2. P2P trading platforms - there is additional 'fee' when you want to buy bitcoin in a more anonymous fashion.
3. This tool is probably the best service where you can quickly estimate average price of BTC -
http://preev.com/btc/usd