BluRay and HDDVD don't really interest me, but I do rip *all* DVDs that pass through here.
Not for a hard drive library -- the discs themselves are fine for that -- but rather to remove all of the stupid "can't press FF now" type of restrictions from them before playing them, and also to "fix" the odd few that don't seem to be playable under MythTV by default (weird, that..).
But DVDs for me are not like music -- they get played once, twice maybe, and then not again for years. No need here to have them always "on line".
Cheers