I checked this book out after I heard that Brandon Sanderson was picked to finish the wheel of time series, had no real expectations as he was a new name for me.
The story at first glance may not seem terrible original:

The world has been ruled for a 1000 years by an seemingly immortal God/emperor,the Lord Ruler, who according to the legends was a great hero who vanquished a world threatening evil before taking power.
Now he has divided society into Noblemen and Skaa, a slave class seen as subhuman by the nobles and treated accordingly.

The major difference between nobles and the skaa is that the nobles
can be born with a magical ability to increase their strenght,speed,senses and manipulate metals and emotions by "burning" the metals in their body.By eating/drinking flakes and solutions of metals they can replenish the metals they use while "burning" metal.
Different metals have different properties, and usually the ones with the talent can only manipulate one of these,and are called misters. Howewer, some,called mistborn, are able to use all metals, and are essentially superhuman, often used by the noble houses as spies and assassins.

Although hunted, the Skaa also have some misters and mistborn being bastard children of nobles straying outside their class.

A Skaa Mistborn, a former thief having awakened his powers while escaping a slave mine where no one has escaped before,gathers a crew of Skaa thiefs and rebels with a plan to destroy the Lord ruler and conquor the capital.
Essential to his plans is the 16 year old girl Vin, who unknown to herself living as a thief on the streets, is also a Mistborn.

I quite liked the magic system in this book,the metal "burning" system feels both new and fresh, and is well conceived and used. The writing is good and fluent,with both humour and action sequenses that work, the characters are interesting if sometimes a bit shallow.
The story feels familiar for anyone who's read some fantasy and sci-fi, but still works.
Overall a good read and a interesting premise.