basic light & dark variations. I'm partial to natural color patterns like white belly, gray top, with a streak of pink or blue down the side. For dark nights, black, olive green, blurble, etc. In my opinion though, proper presentation & using the correct profile to match the what baitfish may be in the area is usually more critical than the color of the lure.
Read these threads:
The Color Of Money
Presentation Oddities
The 2x2 Matrix