This book has actually only been issued in August 2010. And it's usually considered to be the second (not third) edition. Though there was a predecessor to the first edition which - in addition - had covered North Africa.
I should first say that I'm collecting field guides whether I'll ever have a chance to go to a certain area or not. And my preliminary judgment thus is based mostly on optical appearance and not on actual accuracy. I'll leave that to others who are better acquainted with the area.
My first feeling with this new edition was kind of WOW, what a fine and attractive book. I have the first edition as well, so I can compare. I definitely like the new arrangement and the more informative distribution maps. Most illustrations have been retained from the first edition, but they are often larger now as the plates are now much less crowded. Just as an example, there are now two plates for the seven species of nightjars. In this particular case, however, I liked the possibility of comparing all the species on the same page in the first edition. In many other cases, the spreading over more pages has been most welcome, however. Some species illustrations have been redone without any obvious benefit as far as I can see. A case in point being the sandgrouse, though the larger illustrations per se are welcome. In some cases, the new illustrations are of quite inferior quality as far as I'm concerned. In particular, I think the terns are now of a quality like one could find decades ago. It's mostly the proportions in the flying birds that I think are off in several species, way too slim. It's because of such cases that I give only four stars. Actually, it would deserve a bit more, but not five.
In at least one case, the first edition had an additional illustration. Thus the flight picture of the Rufous Turtle Dove is now missing.
Some confusion arises when comparing species names.
Thus, again just to list one example, I first thought the Indian Hawk Cuckoo Cuculus varius was missing. But it is still present, it only changed both names to Common Hawk Cuckoo Hierococcyx varius. Another case of the disservice modern systematics does to birders.
The text is opposite the plate, combined with the range map. But the information is still about equally complete as in the first edition where the text was on separate pages. Well done indeed.
The paperback version may not be as sturdy as its hardcover predecessor. But it is definitely more compact.
In addition to following a new species sequence now (which needs some getting accustomed to, but is no real problem), the systematics of the large gulls has been thoroughly updated, with a fine series of new illustrations as well. An interesting new feature is a special spread called Comparison Plate for the large white-headed gulls. It includes a moult table.
There is another additional feature, a plate called Non-native Weavers, Bishops & Allies. Species on this "escapes" plate get less text and no range maps. Thus, the Red Avadavat has now lost its distribution map compared to the first edition.
Finally, a most welcome change is the fact that the illustrations from plates 111 and 112 of the first edition have now been integrated into the regular sequence. Thus, one is less likely to overlook the fact that there is an illustration of some rarer species or vagrant, like the Egyptian Plover or the Lesser Moorhen.
There is some unnecessary irritation in the arrangement of flight illustrations in some few cases. Thus, in both plates of the nightjars, there is one species that has the back and bottom views switched. As illustrations had to be rearranged anyway, it should have been possible to deal with this matter. It was the same problem in the first edition, but because of the way these pictures were arranged there, the irritation was not that obvious.
Overall, I consider this new edition a vast improvement, well worth buying even if one already has the first edition.