I'm not remotely qualified to review this book as a work of scholarship, but I can recommend it as an enthusiastic amateur. Trudgill's primary audience is clearly other linguists, but his prose is accessible and engaging. This resolved a lot of the confusion resulting from my very 101-level understanding of linguistic change, most of the questions it answers are ones I've never thought to ask. Now I want to check out the author's work on British dialects (and possibly learn Faroese).