I personally think you should definitely include this in your optional essay.
quote="accincognito"]I plan to apply to NYU Stern but have a GMAT score of 670. I have taken already taken the GMAT 4 times (500-580-650-670) this year
and taking another one on 28 November 2013. Since the deadline for 2nd round Stern is on 15 Nov, I was wondering whether I should include a paragraph in my optional essay regarding my plan to retake the GMAT.
Thanks for your recommendation in advance.[/quote]