I certainly am not.
I picked the PS3 because I liked its exclusive games and features the most. I didn't flip a coin or draw the Playstation logo out of a hat. I was a PC/MMO gamer at the start of this generation; when I decided to move away from MMOs, I asked around and researched the three console choices before going with the one I found to be the most personally appealing.
Previously, my best friend and I stuck with MMOs because they offered the best way to play together. When he passed away in 2008, my heart completely went out of social gaming. I struggled on with it for awhile but it just wasn't the same. Having paid zero attention to this generation before that, though, I feel like I was objective, relative to my own preferences, in my evaluations when I decided to make the plunge.
With that, I have nothing against Nintendo or Microsoft. I still have my NES and SNES, and it's almost impossible to be a PC gamer without Windows. So, while I'll defend Playstation if I disagree with a detractor, I'm certainly not one of those who attacks the consoles I don't have. Honestly, if it was in my budget, I'd almost certainly buy a Wii U, and probably a 360 for Halo.
I do admit to having some hard feelings against the Nintendo fanbase, though, that I've had to struggle to overcome. Before I bought a console this gen, when I was still weighing the pros and cons of each, I pretty much got ambushed by Nintendo fanboys and it left a bad taste in my mouth. On random forums that were apparently much less mature than here, I would ask for opinions and recommendations; with the Wii, I unwittingly ran into a hyper-defensive buzz-saw. When I said that I didn't care that much for Mario or platformers in general, things turned bitter. I got a lot of personal insults over that, which bothered me for awhile.
Still, I do my best to be objective toward Nintendo and Microsoft and the consoles themselves. Because I like Playstation doesn't mean I have to hate, or even dislike, anything else.