The PS3 has so far attracted very little of the huge array of visual novels available on the PS2, and it appears this is for a reason, according to a recent magazine report on the subject.
The three reasons given are these:
1. The title needs to sell over 30,000 copies (visual novels can be lucky to sell 10,000)
2. Some sort of online features are supposed to be included.
3. HD graphics should be supported.
There is certainly a ring of truth to these, especially the first, although there seem to plenty of exceptions to the other “rules.”
Any explanation which does not take into account the lack of these features in other titles, to say nothing of the huge installed base of the PS2 seems incomplete at present…