If you shoot people, pair it with the 45

As one reviewer said just buy it.

Another said "if you have a use for it".
If you shoot people, landscapes night street scenes, indoor sports, theater and other performance art, you HAVE a use for this lens.

To let some pictures do the talking first ...

Some people samples ..
Kids
Littlies ..

Some Low (sometimes extremely low) light samples

Music - I couldn't even SEE some of these musicians esp the camera tech lady, I saw only a silhouette.  THe OMF VF to the rescue.
Footloose
The 75 (and 45) make THIS easier

DON'T listen to non-oly-user trolls who want to:
. make pseudo-relevant mathematical "arguments' about photons instead talking about of pictures
. tell you that it is not a useful "people" focal length (it is superb)
. that you cannot get shallow enough depth of field (you can, AND sell your pictures as well, if you have worked hard enough).
. that 85 is the "ideal" focal length for portraits of people - rubbish, I know pros who use 8 degree AOV lenses for fashion shots. That's 300mm in FMF (Full Marketing Frame.

If you need wider or don't have room, also consider the diminutive 45/f1.8, which is close to the "correct" 85mm in FMF.

DO:
. Have a look at the results others obtain.
. Borrow one if you're still unsure.
. Realise that results this good are not found in the bargain basement
. check out people like this who logically debunk the "need" for larger sensors for most work

. Facing the fear generated by good marketing
. More samples

The detail available with this lens and the new Micro four thirds sensors is incredible.
The handling in real-world situations excels.
The 75 gives a flattering perspective for people.

The 75/f1.8 is excellent for timid subjects and helps you get the BEST out of first time models.
Why? Just a little more distance puts the subject at ease.
If someone contracted me to do a billboard that actually needed MORE resolution and had to be shot in on frame, I MAY ask for a large advance and MIGHT get a FMF camera and 2 fast primes.  Very few photographers need to make that huge weight/size concession to do good, saleable work.
A bazooka/brick combination left at home shoots NO pictures at all.

I have posted a selection of test pics including 1:1 crops (amazing what this lens can 'see', with an OMD, that goes double in very dim light.
Interested buyers can satisfy themselves more easily that it is a great people/landscape pet-sized animals and larger birds (among other uses).  Rabid critics are welcome too ..

The lad was shot on a dismal "almost no contrast day" it rained (a flooding event, actually) just 5 minutes after they were shot.  
The images COULD be processed  but I decided to leave them substantially as is, so you can see the lens capability in poor light, not my box of tricks.
Anyway ... you can see EM-1/Zuiko 75mm/f1.8 simple, unprocessed test shots (shrinking, colour and density only)   WITH crops - here...
http://photohounds.smugmug.com/Gear-tests/Zuiko-75mm-f18/
Oh yes, as in most of my galleries .. If you press the "i" (as in info) circular button, mid-bottom right, most of my pics have exif data.
Comments can be left on individual images.

YMMV according with your "pigmentation". (I might get banned for this one) May the spirit of Lenny Bruce help me!