LX7

http://www.dpreview.com/reviews/sony-cybershot-dsc-rx100/

I think that's a pretty good camera with a good lens for portrait and good for low light because it opens to f1.4 which is the widest!  It's a new model.  Historically, the LX line from Panasonic is very popular and good size compact camera with lots of serious features that put the pros use.  Leica lens on the Panasonic is very quality German built glass.  So that's a plus. 

The above link is the Sony rx100 review.  It has similar features.  It has a larger sensor then the LX 7, for the same price range 500 to 600 as the Panasonic LX7.  Sony just came out with an update model to the RX100 call the RX1: 
http://www.dpreview.com/product/sony/compacts/sony_dscrx1   

This camera has the same full size sensor as the big Digital SLR in a compact size.  It's a bit more expensive.  Also, the lens does not zoom which can be negative because people like to zoom in closer for pictures and portraits.  But for snap shots, you really don't need a full size sensor.  The sensor just picks up more detail for people who want to print big.  So, I think the Panasonic LX 7 is a very good buy.  I really like the large apperature f1.4 lens on the LX7.  It lets in a lot of light for night shots without flash.