Just thought I'd post something I found interesting.
Sage Advice Column in Dragon 327 - "A character with the hide in plain sight class feature (described on page 48 of the Player's Handbook) can make a Hide check even if he's being observed. This doesn't require any extra action to accomplish (unlike the sniping maneuver)."
The article then goes on about HiPS and attacking (saying that with HiPS you can make melee attacks and remain hidden with the -20 penalty). However, what I find really interesting is that the article basically validates the Full Attack while Hiding in Plain Sight Shadow Dancer