Somewhere, and I won't say where, a proofreader is about to earn her pay. I've had the privilege of reviewing a number of novels over the years, many in the ARC stage. The quality of the stories has varied, of course, and they all have a few errors. Who hasn't read even the best of books and not found a typo here and there? This is an especially dangerous problem for self-published work, but the best publishing houses are not exempt.
In the case I have in mind, the scheduled pub date is early 2012, and the author teaches writing and literature at a reputable college. The story he tells is a good one, full of twists and turns, terror and excitement. But the typos! I have never seen so many typos from a mainstream publisher, even in an ARC. We have many instances of characters pouring over records instead of poring over them, and scrapping when the context calls for scraping. At first it looked like someone over-relied on the spell-checker, which only flags misspelled words, not incorrect ones--and then came "dispite" and "underware," which never should have left the author's word processor. There are many more bloopers, but the worst one involves a character named Kurt. Use your imagination.
Perhaps a diligent proofreader will catch what needs to be caught. Perhaps she won't. My point is not to belittle anyone, but to warn writers to scour your manuscripts and galleys. Don't bet your reputation on someone else cleaning up all of your mistakes. The cleaner the manuscript is to start with, the less a proofreader can miss.