I think Susan Miller has won my astrological heart! I always buy those "gemini 2011, 2012, etc." books and even though they are for your specific sign they always leave me wanting more (also they're too short and not worth the $9.99 you're probably spending!).
I started out just checking my monthly horoscope on her page www.astrologyzone.com and came to realize that she had the most accurate horoscopes around. I understand that some people don't really believe in that sort of thing but even if you just glance at yours for fun, Susan Miller is still the best. Anyway, I started checking into her book and noticed all these rave reviews for her (not just her books), she has a pretty large fan base from what I've seen. A ton of people swear by this lady.
I'll just tell you from my opinion that I'll never buy another random yearly astrology book again, from now on I'm Susan Miller all the way!