Well, in terms of hardware the original Xbox was quite a bit better than the PS2 (including an internal hard drive as opposed to memory cards), allowing for PC ports like Doom 3 and Half-Life 2 which the PS2 simply couldn't handle. And of course it brought Halo 1 and Halo 2, two great exclusive titles. But the PS2 has its own fair share of exclusive games so I'd say I liked them both the same.
Now, the PS3 console itself is superior to the Xbox 360 in practically every way, the hardware, features, etc. It also doesn't have an inherent fault like the 360 (RRoD). Xbox Live is a massive rip-off full of P2P servers, while PSN is free and full of Dedicated Servers. PSN is actually better, but people think "you get what you pay for" and that's not that case here, Microsoft are just greedy.
But it really comes down to the games, and in that department the PS3 starts to falter due to the PS3's strange 8-core design and architecture it means games are harder to make for it, which results in lower quality multi-platform titles, mostly in terms of graphics when compared to PC or 360. However, when dedicated PS3 develepors like Naughty Dog who know how to develop for it make an exclusive title like Uncharted 2, Killzone 2, LittleBigPlanet, etc, it really shows what the system is capable of.
I like the exclusive titles of PS3 & 360 equally but I still sold my PS3 so I could build a PC for gaming, which blows any console out of the water, but that's another matter.
