Here is my two cents worth on this topic.
Leupold - Beaverton Oregon - Lifetime Warranty Transferable
Burris - Greeley Colorado - Lifetime Warranty, Transferable
Nikon - Japan - Lifetime Warranty Warranty.
Call me a homer, or stupid, or whatever but I will always buy US made products and pay a little more, if the choice is there to make.
If the only choice was Nikon or Burris I would take the Burris. If the choice was between the three I would take the Leupold. If you want to give me any of the three, I would not complain.
Make sure when comparing scopes you compare like for like.
Leupold Rifleman and VX-I, Nikon Pro Staff
Leupold VX-II, Burris FF-II, Nikon Buckmaster
Leupold VX-III, Burris Signature Nikon Monarch
Leupold LPS and VXL, Burris Black Diamond, Nikon Titanium
Leupold and Burris have custom shops. You can have the reticles changed to your liking. They are first and foremost Scope manufacturers. Nikon makes cameras. The clarity and light gathering abilities are about the same on all three. The customer service provided by Leupold is excellent.
I bought a Leupold VXII 3x9x40 for $225 last week off of gunbroker.com and saw the same scope sell on Ebay for $227. (way below wholesale) Both were new in the box. I know where to get all three types wholesale if you are interested. email me for details.