AntiVirus & Windows 8

I'll be purchasing a new W8 laptop by the end of the year and want to be prepared.

I currently use Norton Antivirus on my current Windows Vista laptop. I feel like it's a resource hog, however I must say that it seems to work incredibly well and I haven't had any virus issues since I started using it a few years ago.

My question is: Should I continue to use 3rd party Antivirus software (such as Norton)? Is the built-in virus protection enough?

POST RULES: Please do not respond with "Norton sucks!" or anything along those lines. I am hoping for responses that answer my question about built-in protection Vs. 3rd-party protection. Thanks!