This is not my update, but friend of mine was upgraded.
Two separate tickets with different origins (Europe/Africa)
I was in J, she in Y.
We decided to meet at the airport just on entrance to the gate, had a chat before going to the gate and still chatting we have presented together our boarding passes to gate agent (I was waiting a bit longer so we can board together with other Y paxs). He asked us if we are together. After a short while a friend of mine was given new boarding pass with seat 9K (actually she was not aware about it until I told her that she is now in business class). Note: I was not asking for upgrade for her and she was previously not aware that I'm in J.

Route: DXB-GIG
Upgrade location: Gate
Upgrade given: Y - J
Date of travel: JUL13
Tier status: None?
Tier miles to date: 0
Skywards miles balance: 0
Number of pax on the same PNR: Single
First letter of name:N

BTW. J had 100%LF so seat 9K means that probably someone was upgraded to F. On the plane nice pax changed a seat so we were able to sit together.

lucky day and I'm really grateful for that guy at the gate.