This book, written complete in sonnet verse is simply amazing. When you open the cover and discover that not only, the main text, but the Acknowlegments, Table of Contents, Dedication, and "About The Authour" are also written in sonnet form, you'll know that Seth means business.
The entire book is written in Iambic Tetrameter (with strict rhyming to boot), yet though I thought this would be forboding, it really wasn't, and is amazingly readable. You'll even find yourself, having put the book down, thinking and talking in the line length that the authour uses!
The book itself, details the lives of a close knit group of Californians, initially centering about a programmer (though the omnisient narrator darts around a bit) and his life, relationships, and the waxing and waning of his friendships. Seth achieves this with utmost brilliance as the protagonist falls in and out of love, even venturing into brief promiscuity.
The Golden Gate ends with a few broken hearts, and is indeed vaguely depressing towards its finale. Seth's style, however, is true to the end, and indeed it is a well recommended read (even if just for the experience!). Just pick it up and be immersed - you won't be able to put it down.