It would help if there was a wiki page on format shifting. I used to add something like "may not be legal where you live" to my posts on ConvertLIT (say). This was not a comment based on the location of the original post but a generic comment that legality varies from place to place. I stopped doing so because of the extra typing involved, but I would be happy to add "see format shifting in the wiki" where appropriate. Note that I am not suggesting that the wiki point to tools for format shifting (although the conversion page already does), but rather that it discuss the legality of the practice.
The legal situation isn't always black and white, In the US, format shifting for personal use is legal (a fair use) except when it involves stripping DRM. If it does involve DRM, then my understanding is that some federal district courts have held that DMCA trumps fair use and others have not said one way or the other. So its legality may depend on where in the US you live. See
Question: What is the effect of the anti-circumvention provisions on the traditional defenses to copyright law?.