The problem is that the internet has a VERY long memory...not just "nudes", but other items as well. Once its out there.... there really is no way to get it back...
Just a one example.... Many people that used to post on USENET in their "younger" days are now finding that items that they had thought were LONG gone off the USENET "spool" are now coming back to haunt them. This is because when google first started its google groups service, one of the items that they had done was to purchase old backup tapes of USENET posts and indexed all of that into their engines. Google bought Deja-News and other usenet providers to gain access to the data. Suddenly stuff that normally would have been gone in 18months is now available to search/find.
The only way to post nowadays to assume that the information will be seen by the ONE person you may not want to see the info in 5-10-20 years.. So be careful what gets out there...Slashdot included.