Eventually, the prices will increase back to the previously high amount but probably not for a long time. Obviously inflation over the next 20 years will warrant an increase in the price but also demand will continue for oil and we will continuously be in search of cheap oil and depending on where we need to acquire that oil will dictate the cost of it.
Oil prices are currently down because the United States and Canada are now producing some of it, and demand is dying down in some countries. That being said, the nature of it is that it fluctuates. It's an issue of supply and demand. Eventually, while it's not guaranteed, it's likely there will be higher demand and less supply again, in which case the prices will go back up.
If you look at the long-term trends in oil prices it is obvious that there are ups and downs to the commodity. Currently, the oil surplus is driving prices down, but by mid-summer we will see oil prices climb steadily, possibly even higher than levels seen before. The oil market has these ups and downs and has had them for many years.
Many people debating the price of oil and whether or not it will go back up have forgotten one important fact: oil is finite and will one day run out. Consequently, while it may not be likely that oil prices rise significantly in the short term, or even in the next five years, once oil supplies begin to run out for good, then the prices will surely go up.