Translated, nota bene means note well. In many articles, it serves as an editorial note or "p.s." at the end. From this Zagat FAQ:
In present-day English, it is used to draw the attention of the reader to a certain (side) aspect or detail of the subject on hand, translating it as "pay attention" or "take notice."This Gothamist article is an example of N.B. in action. You'll see that Gothamist's Dobkin provides a long answer with additional notes at the end.
Nota bene, Wikipedia
What does N.B. mean?, Zagat Help