[RcGrant]

That last comma before the 'and' is called the Oxford comma. As far as I'm aware, the general inclusion of it is personal choice. I love it. To me it looks far cleaner than not using it. I think (though don't quote me on this) it's more common not to use it than to use it, but it does boil down to personal preference. I'd suggest as long as you are consistent then it's not going to matter.