I made a documentary on porn and women: we did a survey on the net to ask users why they liked porn, and what they would like to see. We also asked non-users what put them off. The top five reasons were as follows:

1)Boredom(nothing of interest in it)
2) Bad taste (big hair, ditsy women, orange makeup, ugly guys, stupid expressions)
3) Lack of eroticism
4) Distaste for porn in general
5) Lack of imagination(always the same scenarios)

Yes, porn is manufactured to suit the male taste, and thus there is very little on offer to amuse or entertain females. The women that did like porn expressed in the main(78% of users) a preference for lesbian porn.

I think this is due to the sexualisation of women's bodies in the media. Women's bodies are used to make products look sexy: as a consequence of this, the naked female body is immediately recognisable as a sexual object. The male body has not been sexualised in the same way, except in gay male porn or gay male magazines - which women rarely see. Naked male bodies are still a rarity on TV, and it is still illegal to show the erect penis on British television or in films.

Therefore, many otherwise heterosexual women feel turned on by seeing naked women..