If you are looking at the current crop of half ton (150/1500 series) trucks, the good news is that there are a lot of good choices out there. The bad news is there are a lot of good choices out there :). Tough to make a decision.
You really can't go wrong though. Ford, Ram, and General Motors all make great half ton trucks. Drive them all and narrow it down to a brand, then we can help by suggesting engine and axle ratio choices based on which brand you prefer.
The GMC/Chevys have the 5.3L V8 and 6.2L V8s, Ford has the Ecoboost turbo V6 (2 different ones coming for 2015 -- a 2.7 and a 3.5L) and 5.0L V8, and Ram has the Ecodiesel turbo V6, V8 Hemi, 4 corner adjustable air suspension, 8 speed auto (others are 6) and the Hemi V8.