than vs. from

I have seen the phrase "different than" used, incorrectly, several times over the last month (here on E2, and in other media). This is an understandable mistake for non-native English users, but most of us should know better.
The only time it is appropriate to say "different than" is when you are comparing the different-ness of several things with respect to another thing: "With respect to pears, oranges are more different than apples". Beyond this unusual comparative use, it is proper to say "different from": "Apples are different from pears, but oranges are even more different from pears than apples."
The example of misuse at hand is the CD sleeve from Dr. Jeffrey Thompson's Brainwave Suite - Delta CD: "...audio tapes which are entirely different than anything done before." If the usage had been "...more different than anything...", "than" would be correct (if sloppy); as it stands, it should be "...entirely different from anything..."
Remember: when comparing the extent of difference, use "more different than" or "less different than"; otherwise, use "different from".

According to Dictionary.com, "different from" and "different than" are both accepted uses in British and American English (also accepted in Britian is "different to").

It seems to be a long-standing debate, and there are usage rules for when to use "different than" and when to use "different from," so there is a distinction made, even by those who believe "different than" is a correct form.