why are people complaining about OMD button size ???

Some people feel a need to complain I suppose.

The buttons are small, yes, but so is the camera.  I gave up my DSLR to get a smaller lighter camera - that's exactly what I wanted.  Don't want small buttons - buy a bigger camera - life is full of choices.  I have large hands, and I have no problem with the buttons.

The only buttons I would call "squishy" are the 4 directional buttons.  The "squishyness" apparently is the result of weather sealing.   Frankly I never noticed it until seeing complaints.  It still doesn't bother me, has zero impact on the camera's operation, and I like that my camera is weather sealed.

The only minor complaint I would lodge is the AEL and FN1 buttons are a bit too close together.  A little more separation there would be nice.

As DPReview states, operating the smallish buttons with gloves on would be a problem, but otherwise; complaints about the small buttons is nonsense IMO.  If you want a DSLR sized control layout, then well, buy a DSLR.