When Four thirds or Micro Four thirds cameras were first announced, they were quite limited in native Auto Focus lenses. Sure you can adapt other lenses, but the size and speed of having an actual four thirds lens can't be substituted. In the last few years, the MFT camera lineups have grown and so has the availability of different lenses.
Two new micro 4/3 Prime lenses that people are anxious to grab is the new 12mm F/2.0 (about 24mm) and the 45mm F/1.8 (about 90mm). If you're not too familiar, these lenses also work on the Panasonic GH1, GH2, GF2, G3 type cameras. It's all Micro Four Thirds. These new lenses fill in some of the gaps that have been missing in the lens lineups, and further reiterate that small mirrorless cameras are in demand. (Rumor is that Canon already has one in the pipeline).