The NY Times has an article about how hi-def porn may be too detailed to be sexy. I’ve heard this argument going way back – I think first when big screen TVs came out.
It will make for some interesting cosmetic surgery news though:

Jesse Jane, one of the industry’ss biggest stars, plans to go under the knife next month to deal with one side effect of high-definition. The images are so clear that Ms. Jane’s breast implants, from an operation six years ago, can be seen bulging oddly on screen.
“I’m having my breasts redone because of HD,” she said.
The stretch marks on Ms. Jane from seven years ago when she gave birth to her son are also more apparent. But she deals with those blemishes in a simpler way: by liberal use of tanning spray.