I'm not quite sure but I think I discovered LPL after my first Linkin Park concerts last year. I got to know Mark and Jonas in Zuerich andI'm pretty sure that this was the reason why I joined. Two days later I ran into them again in Stuttgart. Mark pretty much made me ask Mike in Stuttgart to play Reading my eyes, I would never have done that on my own, so even before I officially got to know LPL, it already influenced my personal experiences with Linkin Park, and I'm still very thankful for it. I'm not listening to LP for such a long time yet, I think I started with MTM, but last year was the point when I joined the Linkin Park community, started to go to concerts, to collect things like CDs and live shows - and not at least due to the last point, LPL was a great help. I really like, how it's possible to look up almost every past concert, check the setlist and also if something special had happened during each specific concert. Above all, LPL was the first homepage where I got to know other Linkin Park fans, so LPL pretty much increased my addiction and made me addicted in the first place to the band.
There are other amazing fanpages out there, but no matter how great they are, LPL will always be the homepage that made me discover how amazing Linkin Park is, and that's because I got introduced to Mark and Jonas last year.