This was on another post, but I believe the consensus was very regular oil changes no matter what oil you use. In a poll taken a few weeks ago, synthetic oil was prefered at about 60% over conventional oil.
Personally, I change mine every 3k miles and us Mobil 1
2007 LT 2.2
GMPP Air Intake * GMPP Extrude Honed Manifold * GMPP Cat-Back Performance Exhaust * Vibrant D/P * Jet Stage 2 Module
MOBIL 1 Synthetic Oil * DC Sport Strut Tower Brace * Color Matched Mirror Covers * EuroAntenna * 30-15 3M FX Tinting
Bridgestone Potenza Pole Position RE960AS on Premium Wheels
2.4 Intake Manifold Conversion * 2.4 TB * TUNE