I think it would be stupid of Sony and Microsoft bring out a newer console now, because there will be no driving factor for me to buy it. My consoles so far:
PS1 - Had a CD player, so I could listen to CDs in my room.
PS2 - Had a DVD Player, was handy when DVDs were the latest thing, and games could be bigger in size and hence better.
PS3 - Has a BluRay player, which I now use in my Home Theater as a BR player and media player
So, If they bring out a PS4 now, what would they put in it? A BluRay player again? I believe that a HUGE part of why Sony get the large amount of sales, is due to the BR player, and that the console is damn sexy and looks great on any TV stand.
XBox made a huge amount of sales, due to the fact that you could hack it and play copied games(feel free to replace aforementioned jargon with the correct). A friend of mine has 2 of these, one for online play, and another hacked one with no internet access to play the copied games on. Also, his latest XBox is his 5th one, so if MS count clients in stead of units.... What I meant to say is, there is also no upgraded media that XBox can use in a Next-Gen console right now.
PS: I will believe in a PS4 when I see it on Sony's site

Also, that boomerang controller looks fugly, but may just be cool if it really works like a boomerang and comes back when I get a Mortal Kombat Shao Kahn bitch fit...