It's important early in a console's life. I never had a PS1, so when I got a PS2 and the only game I had for it was SSX, it was nice to have a huge library of titles to choose from while the PS2's was slim pickins.
It becomes less important later in a consoles life, particularly with the sequelitis publishers have these days... you're almost guaranteed a better looking version of the same game on the new platform.







