So I got the book at my local game shop (they special ordered it for me) and I instantly began reading up on the Spinward Marches. Now I'm a new fan to Traveller and mongoose is the only edition I've bought so far (though GURPS is at my local store and I might start collecting it). So far I love the OTU and the Spinward Marches is considered the starting point for any new player.
Now the book itself is well writen and set up nicely. The intro gives you a strong idea of key elements within the Traveller Universe (TU). Within the first 10 pages you will learn a lot and most of the book is subsector maps mixed in with world descriptions and history of the region, a lot of what you'd expect. So the writing gets all five stars in my opinion. Now why then did I put it up for four stars? Because sadly the artwork isn't up to par with what you'd expect from a $30.00+ RPG book. Honestly some parts of the artwork, though good are just plane amature. I went to art school myself for a year and a half and I learned many of the basic elements of drawing. Some of the art towards the back of the book looks like a first year art students work. Its not bad its just under developed.
However no RPG pen and paper fan should judge a book by its art but rather by its content and mongoose traveller is packed with good content. If you have a strong imagination then the art shouldn't hold you back and I only subtracted a star because older edditions of the Traveller series have had some truely wonderful artwork in them. Overall if you're a new traveller fan then pick up Spinward Marches. Its a solid and well writen section of the OTU for you and your friends to play around in.