Squeeze Release BSP Marathon
For details about what a BSP Marathon is see Debian-Devel-Announce. It might be also a good idea to have read the HostingBSP howto. It gives some ideas what background work is needed to host a BSP.
Some useful links:
Etch Release BSPMarathonEtch
Lenny Release BSPMarathonLenny
2010 BSPs
Boulogne-Billancourt, France: BSP/2010/12/fr/Boulogne-Billancourt (December 4-5)
Bern, Switzerland: BSP/2010/11/ch/Bern (November 27-28)
Manchester, UK: BSP/2010/11/gb/Manchester (November 13th-14th)
Paris, France: BSP/2010/10/fr/Paris (October 30-31)
Berlin, Germany: BSP/2010/07/de/Berlin (July 19th)
Munich, Germany: BSP/2010/07/de/Munich (July 16th-18th)
Bordeaux, France: BSP/2010/07/fr/Bordeaux (July 6-11)
Khon Kaen, Thailand: BSP/2010/03/th/KhonKaen (March)
New York City: BSP/2010/01/us/NewYorkCity (Jan 29-31)
Mönchengladbach, Germany: BSP/2010/01/de/Moenchengladbach (Jan)
2009 BSPs
Cambridge, UK: BSP/2009/11/gb/Cambridge
Munich, Germany: BSP/2009/11/de/Munich