This picture first made the rounds in December and Chris Timm posted a note to our off-road tandem forum that filled in the background. Relevant extracts of the note are appended below:
"The pic was taken at Team Telekom's pre-season presentation, an annual get-together topped off with an MTB race of the team against journalists. They [Ulrich & Zabel** are riding a Soil 'Hard Line' FS MTB tandem. Soil is a brand name used by the traditional German bike manufacturer Schauff, a large family-owned company. Schauff holds a license to build entry-level bikes under the 'Team Telekom' brand name, so as one of the team's partners they were invited to the presentation and brought a tandem along just for fun. Jan Schauff is on the German tandem listserv, and he hopes that the pic will increase interest in tandems."
The picture was also picked up by one of Lance Armstrong's Web masters and posted to the LA Web site which put it into much wider distribution.
FWIW: Regarding the yellow tandem, Chris previously rode a Soil F/S Tandem and posted what is his admittedly "subjective test report" at the following URL: