If you're going to do a three day split like that, I'd break it down such as:
Day 1 - Chest/Back
Day 2 - Legs
Day 3 - Shoulders/Triceps/Biceps/Forearms
** Abs on all training days
This way, when you're working your chest and back, you're working two opposing muscle groups, so when you're contracting your lats during a lat exercise, you're stretching your chest. And when doing certain chest exercises, you can stretch the opposing muscles of the back. This way, you can superset chest and back exercises to provide maximum intensity, and maximum overload in a shorter amount of time.
You also get to devote an entire workout to your thighs and calves. The legs constitute about half of your physique, so they demand a lot of training. I don't like the idea of training any other major muscle group on legs day, because if I'm as intense as possible, after a good leg workout, I'm spent.
You can make your shoulder workout very intense, and still have enough energy to work your arms. Some people's arms grow really fast, without much work. But most people have to work to develop good arms, so I think they should get their own independent training. The good thing about working triceps and biceps together is that they're opposing muscles, in that, when you contract the triceps, you're stretching the biceps, and when you contract the biceps, you're stretching the triceps. This makes it really good for supersets, because you can make one muscle contract to the max during one exercise, then jump right into another where you're stretching the muscle you just worked. You get insane pumps doing this.
Good luck man
