Ahh yes, I can speak on the Playstation 3.
First off, let me get out of the way that fact that from a software perspective, right now the PS3 sucks. I mean sure, Resistance: Fall of Man is easily the best console FPS ever made, but does that justify the $600 box right now? Not really. An investment in PS3 is an investment in the future, but I'm sure you knew that.
I'll start with the controller. If you like the Dual Shock, you'll love the SIXAXIS. If you hate the Dual Shock, it won't change your mind. Soem people complain that it's too light, but that's such an assinine complaint that I won't say anything more than pointing out that it doesn't bother me at all. Of course, there's also the devious conspiracy that has rendered it rumble-less. This bothers some people more than others. Personally, I never notice the rumble unless it's pissing me off, and I don't notice it being gone now. Maybe I'm just oblivious. The battery life is fantastic I should mention. I've not seen even a single battery bar go down since I got the console two weeks ago, and while it hasn't necessarily been played to death, the controller has been on for quite a few hours.
The motion detection is hard to judge right now, since not many games make sufficient use of it. It takes some time to use in games like Tony Hawk's Project 8, but if you keep with it it becomes thoroughly possible to play the game with one hand, and do fairly well. Much like the transition from the d-pad to analog sticks, it takes getting used to, and takes some practice. It's well utilized in a few games, and it's neat to think about how it might be used in the future.
The console itself is large, but it's also sleek and sexy. Quite as a whisper, you have to be within around 5 feet to hear it at all as it silently blows hot air out of its sides. It's nice that it basically has no wires sticking out of it save for the power and video cables from the back. The power and eject buttons are touch sensitive and really slick, as is the self loading disk slot.
The interface is awesome. It's basically the same thing as the PSP, but much more refined. It does its job perfectly, and I can't imagine it looking better. I'm looking forward to a firmware update of some sort that lets me have a custom background.
The system's multimedia functions are incredible. It's got a really nifty visualizer for audio, a robust video player, and the single coolest photo-slideshow you've ever seen, involving 3D rendered photographs being tossed onto the background dynamically. It will be cool if they add some more options to these in the future, as it obviously has a lot of potential.
The systems online functions seem incomplete and are underutilized, sadly. Sony still promises they will match XBOX Live feature for feature, but right now it's fairly limited. They've managed a unified username, but all the launch titles that involve friend lists don't use the systems friend list. I assume this will not be true in the future, but for right now it's a bit annoying. The Playstation Network store is really slow right now, and the user interface is a bit annoying, but I think it's fair to assume that as more things pop up there and the service gets going, things will speed up and the interface will be redesigned. Also, much like the 360 at first, the PS3 doesn't support background downloading. Most people assume that will be added, but it's strange that it wouldn't be included out of the box after Microsoft learned that lesson. Clans and Entitlements haven't shown up yet, so I can't comment on those. I would, however, like to see them now. Again, it's hard to say because it seems clear the network functions are incomplete and will be expanded, but what exactly we will see in the future is still up in the air, and it's a bummer that what they haven't got them all up and the service is underutilized.
The graphics are basically right on par with the 360, which is especially impressive since the 360 is much more familiar to developers. Some games have frame rate problems, likely due to unfamiliarity to developers, and the problem that a handful of games run at a higher resolution, which is basically unnecessary and is hurting the system. There are a lot of debates about which console has superior hardware, but there are good arguements on both sides and I don't think it's fair to really pass judgement beyond the fact that developers say they are both strong in their own ways, and games will likely look and perform almost identically. Once again, it's hard to judge this adequately since the system is so new (Especially since most of the proposed differences are contrast issues almost certainly caused by video capture methods). A year from now if when it will really become clear.
Blue-ray is cooler than I thought it would be btw. I had become convinced I wouldn't be able to tell the difference between HD and SD on my crappy SDTV, but after watching Talladega Nights and The 5th Element on both DVD and Blu-ray, I can actually tell a clear difference. The colors on Blu-ray are brighter and more vivid, and a fantastically deep contrast is evident even in standard definition.
I will be honest and state that I don't think the PS3 is worth $600 right now. Once the library expands and the firmware updates open it up a bit, I think the value will be much more evident. Also, keep in mind that the fact it uses new technology means that the price will drop exponentially, so it will be interesting to see how much the machine costs 2-3 years from now, after all the awesome games have come out.
I'm happy I have it, I just wish it had more games right now. (Ahh, the woes of a console launch.)