Actually, there may have been several unofficial records set at the Games Convention - most teutonic booth babes, most embarrassing erection at a major trade show, etc.
The actual Guinness Book Of Records people were on hand, though, to promote the Guinness World Records videogame and to oversee record attempts at three of the included minigames.
Its a bit of an odd duck, the GWR game - yes, you can technically break the world record in one or more of the mini challenges (and have these uploaded to the Guinness site), but it is no more or less (actually, it probably is a bit less) impressive than getting the best possible score in any other, actually popular, game.
So, tiny golf clap applause please for Max Schoenemann (virtual Sheep shearing - 5 sheep in just 13.71 seconds!), Florian Mack (Smashing melons with head - 60 in a minute) and Christian Kurka (100 balloons popped in 10.48 seconds).
Well done you.