This is a tough one to answer. For instance the one I probably use the most is my PS3, because it's my main blu-ray/dvd-player (since it gets better picture than my regular dvd-player, which I only keep around because I have some dvd's from other regions which cannot be played on the ps3). I love the menu system, much more organized and straightforward than on the 360, which I just feel is becoming more and more a clutter of adverticing and "please give us another phone number/e-mail adress to further verify your account" messages. But I have more games on my 360 that are must-plays for me than on my ps3. But the ps3 also have older titles available for sale, so I can relive ps1 classics (never had a ps2, so that wouldn't be re-living for me personally).
Then there's the WiiU, which I only have a couple of titles on so far, but each of those are also absolute solid games that I enjoy to the max. The gamepad is my favourite gaming accessory and I really wish I could play more games with it because it makes it so much easier keeping maps, items, etc in check. And the WiiU also has the older nintendo titles available as digital purchases, so it gives me access to most of my favourite nintendo games that way.
And then there's the 3DS which gives me so much gaming liberty, especially bringing my two favourite Zelda titles with me on the go
I tend to play it in bulks, where I will game battery-draining sessions day upon day, and then a while where I just leave it be. But I'm like that with all my consoles, so.
So, I don't really know. Different consoles give different things. But I do see that my opinion is different when I don't factor in games, than when I do.