I never used to name my pokemon, felt it ruined the trade value or something like that and didn't really see the point. That all changed while I was playing Guild Wars. ArenaNet had recently added a feature known as the Zaishen Menagerie, a place to "store" all of the Ranger pets in the game; from that point on, I'd made it my mission to "catch 'em all" and train them up to maximum level. Using the /petname function to play around with my friends, I'd discovered I liked coming up with fitting, unique and semi-creative names for each species (each pet earned its name by level 15, when it's "evolution" stats were locked in).
About that same time, I had finished my playthrough of Pokemon White to completion, and had decided to pick up and play through the Black version. Realizing that Black version would be identical to White, story-wise, I decided to spice it up using the "nuzlocke challenge" rules. Naming the 'mons really helped me feel an attachment to them; it got to the point where I simply couldn't release my fainted pokemon, despite the rules. I shoved them in a "dead" box and left them there as a monument to themselves. Since then, I've nicknamed every pokemon I could.
By the by, my current B2 team (really taking my time to finish) is: Ritchie the Samurott (a semi-obscure Guild Wars 2 reference), Shoryu the Mienfoo in training (and will be the name of my "promo" Torchic in X/Y), Hadouken the Lucario, Cutie Pie the Galvantula, Genome the Eevee (probably going to become Vaporeon or Umbreon), and Boaty the Fly Slave... I mean Swanna.