A "fanboy" is a term used to describe someone who really loves and supports a particular thing, like a movie, TV show, or video game, and tends to be very enthusiastic and biased towards it. Full definition
You see, «net critics established enough to be on any sort of VIP list are professionals — Miramax surely knows the difference between an upstanding member of The On - Line Film Critics Society (OFCS) and the type of fanboy who submits spy reports to Ain't It Cool News. (filmfreakcentral.net)
I hope it delivers and still remember the footage rust shut up Sony fanboys for a week lol (n4g.com)
Back in the PS2 days, I was a rabid Nintendo fanboy who had no interest in playing any other gaming consoles. (shortpause.com)