nintendo will release an innovative and exciting, cheaper console with a small hard-drive and inferior graphics, that microsoft and sony fanboys will call childish and a 'toy' but then it will dominate the sales...

microsoft will release a shiny HD console with amazing graphics and a huge hard-drive, but will probably stick to the 'classic' controller pads...

and sony will just steal everything the others do but fail miserably...

Nintendo will try to make an even more revolutionary system than the wii and will screw up, will be a repeat of the GC.

Microsoft will make another system with another horrible name and will have decent sales.

SONY will learn from their mistakes of the previous generation, but will still make a loaded system that will be very expensive and will not start selling well for a whole year until good games start coming out.

Microsoft and Sony will expand on the Multimedia integration. Overall, I expect their next systems to be conservative. Sony will try to avoid the PS3 trap, aiming at a lower price; still, both consoles will focus on cutting edge CPU and GPU power.
Nintendo's next move is very hard to tell. The Wii's successor will be more powerful and HD ready, no doubt. But will they try to shake up the industry again? Or will they just refine the motion sensing / pointer functions? Wii Fit won't be the only alternative input device for the Wii, I bet N is constantly testing new ideas.
My guess is they'll wait another year or two to see how well the Wiimote concept will be aging - if people grow tired of it, N needs something new.

Won't happen. Nintendo will have bought Microsoft and Sony off the money they made from the weirdos (aka "people who have never played videogames) that bought Wii and DS.

god willing. Xbox wont actually call there next system XBOX 720. I know its just a filler name because we don't know what the real one will be but 720 would be mega lame.

SNESboy, you can't but xbox, you would have to by MS. i know nin is making alot, but nowhere near enough to by ms...

anyway, i think the MS will make another hd console, using motion control much like sixaxsis, but with rumble and would be put to better use.

sony will try a cheaper console, much like the wii. they will have hd capacity though, along with the motion controls.

for nin, i really don't know. mabey averything this gen combined for one kickass machine

I do not think so, Playstation has always been better (as in more powerful) than the other consoles:

PS vs N64

PSP vs DS

PS3 vs Xbox and Wii 

PS2 was an exception, even though it was more powerful than th GC

I think SONY will have a good powerful system but with not as many features as the PS3 so that in can be sold cheaper. 

 Man, I just hope you're kidding... Sure, most games with the Wiimote just plainly "sucks", but Excite Truck... Even my brother-in-law (5-aged) plays it... It isn't harder or tedious... Surely.

PS4 - World ends 2013 according to the Maya's. So there won't be no PS4... .

X720 - Will come Q2 2010, now including the red square of death and SuperHD-DVD which is even more HD then HD-DVD or BR, lol... At launch the line-up will exist out only shooters, and it will have some rip-off wiimote that sucks, lol ... (Owyeah: Some game with a character called: Spartan117 will be on the sytem at some point)

N-6 - Will have an original name! Will feature graphics on-par with X360 and PS3 now... Will have UBERWIIMOTE2CONTROLS!... Will have Nintendo games on em! Will only be out for 3 months, in which there will be shortages... And then, the world ends! So not many people can play it!

World ends in 2012 according to a lot of cultures actually =P Of course it supposedly all centers around the alignment of a bunch of crap in space and I have a hard time understanding why they could figure it out so clearly and yet we seem to have no clue. Still its intriguing...more so than this topic anyways =)