I think people will continue to ask this from time to time, but I think that 3D is prohibitively more complex than 2D game development and therefore a WYSIWYG creation tool along the lines of a Construct 3D doesn't make any sense.
Things like good 3D models and worlds are hard to come by unless you hire your own team or buy them off somewhere. The maths behind 3D games is much more complex as well - and it's hard enough in 2D. Finally, the industry is moving with such speed and momentum with teams of hundreds of developers and artists, it seems unlikely that anything us lot could come up with would ever be comparable to anything you buy off the shelf in a shop. Still, try out some of the links Davo posted - they seem to be doing alright!