This was reported in today's Abendzeitung. The article doesn't detail exactly which record was broken. But it must have been something like "distance diving in cold water without wetsuit".
This news prompted me to take a quick look at other Guinness World Records broken in Munich. According to the Guinness World Records website there are 16. The most interesting include:
World's fastest yodel - 22 tones (15 falsetto) in one second on February 9, 1992, by Thomas Scholl of Munich
You've probably heard of Circus Krone. They're well known in Munich. They're also the world's oldest touring circus, having been on the road since 1904.
The transparent acrylic glass "tent" roof over the Munich Olympic Stadium is the largest roof in the world.
Worst damage toll from a hail storm - A hailstorm that struck Munich, Germany, in July, 1984, caused an estimated $1 billion worth of damage to trees, buildings and motor vehicles. Trees were stripped of their bark and whole fields of crops were utterly destroyed. Over 70,000 buildings had their roofs damaged and around 250,000 cars were damaged by the icy bombardment. Around 400 people were injured. There are a few TT readers today who still remember this when it happened. See post from the archive: Munich hailstorm
Fastest beer bottle opening - 300 bottles of beer opened in 1 min 47 sec by a team from the Unertl Brewery, in Munich, on April 2, 1999. The video can be seen online: beer bottle opening video (the commentator really knows how to build tension)
World's largest chamber pot collection - 9,400 chamber pots collected by Manfred Klauda. The earliest one dating from the 16th century. To be seen at the Zentrum für Aussergewöhnliche Museum, Munich.
World's largest beer festival - This one needs no further comment. See: Oktoberfest.