If you prefer console shooters (or were a die hard console shooter fan), I assume you would (like most console shooter fans) have an Xbox 360. Since that's not an option, I'm assuming that the console shooter doesn't comprise the focus of your gameplay time, so I'd recommend the PC, because based on what you've said I'm assuming that PC gaming is more up your alley.
Whatever works best for you. Personally, I'm debating between 360 and PC, but leaning toward PC simply because I think the PC community will be larger...we'll see after release. But yeah, between PC and PS3 I'd choose PC hands down.