Both are correct. American English favours the comma; I'm not sure if British English has a preference.
There are sentences, where the comma before the "and" is essential, even if you favour leaving it out.
Listing book-titles: Jane Eyre, Romeo and Juliet, and Oliver Twist. (That would be an interesting book: "Romeo and Juliet and Oliver Twist" hehe...)
Then, there are cases, where leaving out the comma before the and causes ambiguity. I like the example given by the Oxford Dictionary of English:
Wrong: "I would like to thank my parents, Anne Smith and God." (it's: "I would like to thank my parents, Anne Smith, and God." - otherwise Anne Smith and God would be your parents.)
So, if you're already leaving out the comma before the "and" by default, there's no reason to change that (but be aware of ambiguities). If you're just learning English, though, it may be easier to make the comma before the and, as you're less likely to produce confusing sentences.