Because two points...
1) My best and happy game age was with PS1 (I started with SNES but became a true hardcore gamer with PS)... then I brought the three major hardware from PlayStation brand.
2) Games... yes I think that PlayStation brand has the more number of best series with Nintendo brand in second place and Xbox brand in way last. Just some games I love there is in others conoles like Halo, Mario, Zelda and Metroid. But I loved PlayStation games like God of War, WipEout, Gran Turismo, all Team Ico, Sly Cooper, Jak and Daxter, Racket, Twisted Metal, Crash Bandicoot, Syphon Filter, Dark Cloud, etc... games, games and games (I forgot a lot).
And I continue PS Fan because the new fantastics games like Uncharted and Demon's Soul (best game of this generation for now).
So for me Sony had the best console games (PS2) and the biggest library of AAA games of history.