Any Way to Activate Win 8 Pro RTM

I have installed Windows 8 Pro RTM on both my new desktop and older laptop. I had Windows 7 Professional on the laptop previously and didnt buy W7 on my desktop as i had an XP license and W8 beta was out at the time and i have been using it since.

Now i am entitled to the W8 upgrade offer, but i really dont want to install the old OS and then upgrade back to W8 again. is there anyway i can avoid all the hassle and just activate Windows 8 RTM?