I agree too - for example Jane Smiley has written a book in each of many genres (historical, romance, family saga, Shakespeare-update, campus novel....) and I always pick up the latest one, knowing that whatever genre she's in, it'll be well written and well plotted.
I do look out for reviews, eg in the Guardian at the w/e I found out about a book about Bloomsbury marriages that I'll want to get. Also word of mouth from friends and other BookCrossers, particularly. Or just wandering around in a bookshop - and I try to go beyond a cursory look at the covers, though I *will* avoid anything that looks chick-litty and have read some that I wouldn't have picked up in a shop because of that!
Liz