Since the MMO Champion boards don't provide stickies, and I often see requests for items to shoot for to maintain best in slot, and the response posts tend to fall through the forum list, I've posted an interactive listing at owlkin.org. Mousing over the items will give you their tooltip, and they all link to their wowhead pages.
This is a living list which will be updated based on new content, such as Ulduar, and by suggestions/opinions of others.
For the trolls: I am by no means claiming this is an end all, cure all best in slot list. This is what I envision to be best in slot for myself as a tauren druid, and obviously items will change around depending on your hit rating. A night elf will also, obviously, have different itemization due to Heroic Presence.