• View > Proof Setup > Monitor RGB
• Edit > Color Settings (or shift-cmd-K)
  • Change RGB working space to Monitor RGB - Color LCD
  • Set color management to off for RGB

Anything else? Anything different in CS3 beta? Anybody with differing opinions?

Update 2007-12-01: Just for the record, here’s the extra thing you have to do for CS3:

Un-check the option to Convert to sRGB in the Save for Web & Devices dialog.