Actually a very good point by lasthuzzah
that I don't think anyone has mentioned yet.
If you consider that a mortgage is paid off in 20 years or even considerably more (what's the max... 30?), the amount you pay now will seem like nothing near the end of the term. While a homeowner is still paying $1500 for their monthly housing expenses, the renter will then be paying $3000. That's a significant difference which must be factored in when considering the rent vs. buy battle.
In the end, the best long-term option is to buy. Pure and simple. If you bounce from city to city and don't stay in one place for very long, perhaps renting is the best option.