This should be out by now but I've seen no signs of it. This link might be of interest as it looks like there may be a converter to go with it. There may be a need to turn your sound off away from this page - some might not like his taste in music
http://www.damianmcgillicuddy.com/finally-able-talk/
Light weight? Yes compared with an 80-300mm full frame F2.8 against a 40-150mm F2.8 I doubt it. F2.8 is a fair sized chunk of glass at 150mm as well. All to keep metal lens dodo's happy. Sad people but on the other hand they probably had complaints from the same people for the use of plastic on 4/3 lenses.
I suppose the converter will fill the gap between this and the 300mm prime which should also be due shortly - metal again but I can't help feeling many people would prefer a very long zoom to a 300mm prime.
John
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