Bigger discs, but for what?

Since Wii doesn’t feature high def graphics or Dolby Digital/DTS sound, what will the additional space on Wii discs be used for?

It’s my assumption that we’ll see a lot more games with full voice acting and possibly higher quality full-motion video sequences than what we saw on GameCube. Maybe Super Mario Galaxy will feature 1,000 levels or Smash Bros Brawl could have 5,000 trophies to collect. Not sure if I’d really want either of those to be true, so how do you think the larger storage medium will enhance Wii games versus GameCube titles?