The DVD vs Blu-Ray debate is being fired up again this morning, as PGR4 dev Bizarre Creations blames DVD size for the reason you won't see different times of day in PGR4.
Speaking on it's offical forums, a Bizarre spokesman said you won't see different times of day for the city because this involves recreating all the textures again (one for day and one for night). Whilst this wasn't a problem for our dev team, it was a problem fitting all this data on one DVD.
http://www.computerandvideogames.com/article.php?id=169199
bad bad press for Microsoft lately
Rockstar Games complaining about the lack of HD in all Xbox for development and now Bizarre complaining about squeezing data on DVD.
PS3 list of feature seem to be worth the price.