Liberal Democrat Coalition Backlash?

Prominent left-wing blog Liberal Conspiracy recently called for "left-liberals to join Labour" and Alastair Campbell also tweeted that it was "good to see Lib Dem defections to Labour still going - keep 'em coming".

Does Google confirm this trend? For the first time, in the week to 15th May, searches for 'join Labour' has generated enough volumes to begin trending in the UK. As a comparison, I've run it against 'join Facebook' and fascinatingly more people have been searching for 'join Labour' this past week.