Effects of adjustment sliders are not visible until the OK button is hit.

I've just realised that I am seeing this in the beta forum, so you can't go back to the previous version.  Did you mean to post this in the release version forum?

Can you be specific about what adjustments this is happening with? 

Is there definitely no Preview box that is unchecked?

Is the document window zoom ratio set to 100%?  If you are zoomed out (less than 100%) then adjustments might not sshow in the document window.  I'm giving this a low proberbility as you seem to be saying that you do see the change after hitting the OK button.

Are you aware of the Layer Panel Options?  If you have the screen space, then the large thumbnail can be super useful.

Screen shots and specific adjustments would help the Development Team give us a better Photoshop user experience, so please give them a chance.