Took me a while, but we worked it out eventually - there IS a "recent posts" search option... they just haven't done a button for it yet. You see those 5 funny "V" buttons up the top to the right of the Welcome message (for logged in users)... well, they are functions that the vBulletin team haven't got around to doing graphic buttons for yet. If you hover your mouse cursor over them, you will see what each one does. The second one is "View New Posts" - that will do what you want it to, and show you all new posts since you last logged on. I might get around to putting my own buttons in soon.
