DSLR magazine wrote on their facebook wall that Tamron is exploring the possibility of manufacturing lenses for the Micro Four Thirds system:
"Finally! Tamron begins to explore the possibility of manufacturing lenses for Micro Four Thirds system. What can I say? ... I told you so!"
The only problem with this rumor is that Sony is a major shareholder of Tamron and is questionable whether they will support any m4/3 lens development (Sony owns 11.08% of Tamron).