I have a small wireless LAN running a box with XP Pro as the primary computer. It has an HP P3005d printer connected via USB and shared to a Vista Business box.
The XP machine prints fine. However, the Vista machine takes forever to print even 1 page docs. Doesn't matter what is printing, it takes 1-2 minutes before it starts printing.
The Vista machine also shares some of the XP's folders and those work fine, no delay in accessing.