Teachers have always warned about the risks of saving all the studying until the last minute, but students often times neglect this advice anyhow. Research has proven that studying less material over a greater period of time is far more beneficial than trying to cram in all the material in at the last minute (Tips for Effective Study).
If we use the Three-Stage Model, we can see why this is; if you review your notes at the last minute, you can only recall so much. Once reaching your short-term memory, you must continue to recite the items repeatedly until they reach long-term memory. This might not be too much of a problem if we weren't limited in how many items we could remember at a time. This means that we must recite only a few pieces of information at a time to insure we are able to recall the information at test time.
The obvious manner in which this applies to my life is that, as a student myself, I have put significant effort and energy into finding the most efficient study method possible. In high school I found myself trying to do everything the day before or the day of; needless to say, I struggled to remember the more detailed pieces of information. However, as I decided to spread out my study time among several days before quizzes or tests, I saw significant improvement in my scores.
I believe the biggest difference in acceptability of cramming depends on the material being studied; if you can place real-life experiences with the course material, you may not need to study as much as you would for, say, a chemistry exam. For subjects such as math, practice makes perfect; for economics (a lot of theoretical examples), look to ensure you have a mastery of understanding over the key vocabulary terms.