A new tournament has been announced for next month in Amsterdam, titled the "Golden Classic". The unique feature of this event is that it will have adjournments after the first playing session, with the game to be completed on the rest days. This is a return to an earlier time where 5 hour playing sessions were the norm, rather than the 'play until finish' system we have now.
I for one was a little sad when adjournments began to disappear, and I argued strongly for the retention of adjournment regulations in the Laws of Chess at the 2008 FIDE Congress (They were kept in the rules btw). In my earlier days as an arbiter, I had to handle a few of them, and while they were mildly irritating, I still felt they were a legitimate part of them game. Of course they did create the odd headache, especially when players would claim wins based on incorrect procedures from their opponents ('K-Q7 you say. There is no Q file on the board and I claim the game'), or simply argue over the venue and time for the resumption of the game.
What I suspect we will see from this tournament are 3 things. Firstly, there will be some games where the players will deliberately mark time until the end of the session. Secondly, the quality of the endgame play after the adjournment will be quite high. Thirdly, there will be more drawn games amongst the games that go past move 40.
Further details and discussion of this tournament can be found here at Chessvibes.