If you are interested in buying a 75mm lens but want first to check if there is an alternative to the just announced Olympus 75mm lens check this list. Of course keep in mind that you have no autofocus on these third party lenses.
1) Dallmeyer 75mm f/1.9 (Here on eBay). This is an extremely expensive lens and I don’t know why it is so. Only crazy guys would buy that :)
2) Leica Summilux 75mm f/1.4 (Here on eBay). Extraordinary high quality lens for an extraordinary price (although it’s still less expensive than the mysterious Dallmeyer). It’s the fastest of all 75mm lenses
3) Zeiss Biotar 75mm f/1.5 (Here on eBay). Fast and also a bit exotic lens made for the Exacta series.
4) Leica Summarit 75mm f/2.5 (Here on eBay). High quality and relatively compact lens. A bit slow compared to the Olympus (f/2.5).
5) Voigtlander Heliar 75mm f/1.8 (Here on eBay). Probably the best alternative of the new Olympus 75mm f/1.8 lens. Same aperture, superb high quality and cheaper.
6) Fujinon 75mm f/1.8 (Here on eBay). This is a very cheap TV lens and I don’t expect the quality to be very good. I wouldn’t buy that unlike your really need that focal length and you have a very low budget.
In short, if you don’t care about autofocus I would go for the Voigtlander Heliar. If you are rich like a Sultan go for the Leica Summilux! But than again, you will probably use it on the $8000 Leica M Monochrome and not on a m43 camera :)