The biggest reason to own a shipping company stock today is the nascent economic recovery. As economies recover, trade should rebound, and that will increase the demand for international shipping. That, in turn, should lead to an increase in shipping rates, which is often measured through the Baltic Dry Index (BDI).
Of course, China is a major factor here as well. China has been a voracious consumer of coal and iron ore in recent years, and it does not seem that these imports are tailing off. Longer-term, it is possible that India could emerge as more of a factor as well, but that is many years away.