BBC reports on a change to UK porn legislation in response to the problem that "extreme porn" is often hosted overseas. Triggered in response to a murder that was supposedly encouraged by violent porn usage, it puts the onus (no sniggering at the back!) on the user of the porn, rather than the supplier.
This might give Wikipedia some food for thought as some of its images might stray into the definitions of the act and the act of viewing Wikipedia might lead a reader into acting illegally, say looking at Erotic Spanking.
It sounds like there is concern that the definition is overly broad and it is still being reviewed.