ePhotozine reviewed the new Olympus 45mm f/1.2 PRO lens:
There is no doubt that the Olympus M.Zuiko Digital 45mm f/1.2 is a superb lens and one that would be a pleasure to own. The factors that come with that really more concern the cost, which is fairly high, and the applications that a photographer might have in mind. A 90mm-equivalent lens is a very useful optic for portraits, landscapes, short-range sports and architectural details. With perfect drawing, the architectural uses are probably as relevant as the potential for portraits.
It will be an easy decision for those with the cash ready or those who have a commercial use.