Some interesting stuff in this looking at it from a Juve perspective:
http://www.theguardian.com/football/blog/2013/dec/18/question-holding-midfielders-changing-role
The stuff about central midfielders returning to being more rounded players (rather than just destroyers or just ball players) would point to Juve being well placed, with Vidal and Pogba, to leap on the 4-2-3-1 bandwagon with the current trend.
Then there is also the observation at the end (which I believe has been brought up here before) of there not being much difference, particularly when in possession, between teams having a defensive midfielder who drops between the two central defenders, and what Juve have, with Bonucci as a permanent fixture between the other defenders.
Of course, just because there is a trend doesn't mean that one ought to try and play the same way as everyone else.
From what I've seen of Man City, who are mentioned a lot in the article, playing Toure and Fernandinho as two fairly energetic central midfielders in a 4-2-3-1 (4-4-2) the
game is left so insanely open and there is such a lack of control that you would be running huge risks to play like that every week.