It's another PR roundabout just like back in April (summary
link). One side claims one thing, the other claims something else, they both use clever language to make it sound more impressive but reality falls somewhere between the two.
You can rest assured that if there was an unarguable lead across Europe falling out of the GfK numbers for either party, they'd be pretty quick to make a song and dance about it.
Besides, one has been on sale in Europe for 151 weeks (December 2, 2005), the other for 91 weeks (March 23, 2007), so outright lead here is a moot point to all but the people who write the corporate gloating.