Since Sony took over the photo activities of Minolta, we observed a considerable evolution on the lens range. There were only lenses from the Minolta original range (mainly on the second-hand market), but Sony associated with Zeiss to build a full-spectrum offer covering more and more and providing a good answer to the needs from entry-level to pro (going through the expert/enthusiast amateur).
Alpha-Numérique has a good and clear summary panorama of this young but rich product line in a French post: La gamme optique Sony / Zeiss.