Why exactly are we criticizing Bing for porn previews?
Yes, Bing's video preview thumbnails display watchable porn. When you search for it. And you have the adult filter turned off. Big blogs, internet personalities like Loic LeMeur, and even Fox News were all over this. Yes, the same Fox News that just proclaimed Apple and Firefox two of the top three search engines.
Wait, why is this a problem?
Bing, like other search engines, tries its best to index content on the Internet. Want in on a little secret? The Internet is full of porn. Full. Think about the fullest thing you can imagine, then fill thirty seven of it. That's how much porn there is on the 'net. Heck, last week (thanks to a 4chan raid) there was even a flood of raunchy videos on YouTube.
You can turn off safe search on Google and the image results will get pretty racy - downright terrifying in some cases. Same with Yahoo - and turning off the filter is WAY easier there. Heck, search Twitter and see what people like Cytherea are tweeting (If you don't know who she is, don't look her up. She's a porn star.).
If you're upset because your children might figure out how to shut Bing's content filter off and wind up staring down row upon row of lewd video thumbnails, there's a simple way to prevent that. Just surf with your kids, and know what they're up to. Getting upset with Microsoft, Google, or any other search provider isn't going to solve anything.
Truth be told, your kids (and you, for that matter) are just as likely to encounter porn by downloading movies or music using file sharing programs like Limewire or Bearshare. If you've never used one of those programs, give it a shot. Search for a popular song. I'm willing to bet that you'll find at least one dirty video in the results.
Yet another reason to not be outraged about porn on search engines: there are plenty of things on the Internet that are really far more objectionable. Hate speech, instructions on how to manufacture drugs and explosive devices, you name it, it's out there - even synchronized Voldo dancing.
It's silly to point fingers at a search engine about something like this. I haven't seen Fox single out any gas stations for having naughty magazines on sale in plain sight, have you?