word choice - Which is correct: "__ is different from __" or "__ is different than __"?

As someone who learned English later on in life, I was taught that different from is the correct grammar to use: this is different from that. However, it seems these days everyone uses different than instead. I know it's incorrect usage, but does the language evolve if the majority wins?

Edit: Some commented different than is American English and different from is British English, both are OK. IMO, this isn't like color versus colour, though.

Than is used after a comparative adjective, e.g. taller than, whiter than. The word different isn't a comparative adjective, unless used in more different than. Logically, it makes no sense to say different than.

Answer

You left out the construction that makes the question more interesting: different to.

The quick answer is that "different from" is always correct and acceptable everywhere, but "different than" is common in US usage (as odd as it may seem for two things to be both different than the other), and "different to" is common in UK usage (as odd as it may seem to have both "different from" and "different to" mean the same thing).

Here's the useful alt.usage.english FAQ entry in its entirety:

"Different from" is the construction that no one will object to. "Different to" is fairly common informally in the U.K., but rare in the U.S. "Different than" is sometimes used to avoid the cumbersome "different from that which", etc. (e.g., "a very different Pamela than I used to leave all company and pleasure for" -- Samuel Richardson). Some U.S. speakers use "different than" exclusively. Some people have insisted on "different from" on the grounds that "from" is required after "to differ". But Fowler points out that there are many other adjectives that do not conform to the construction of their parent verbs (e.g., "accords with", but "according to"; "derogates from", but "derogatory to").

The Collins Cobuild Bank of English shows choice of preposition after "different" to be distributed as follows:

                "from"  "to"    "than"
                -----   ----    ------
U.K. writing    87.6    10.8     1.5
U.K. speech     68.8    27.3     3.9
U.S. writing    92.7     0.3     7.0
U.S. speech     69.3     0.6    30.1

So it's safest to avoid both "different to" and "different than", even though they have ≈30% popularity in UK and US speech respectively, and use "different from" exclusively. See also Michael Quinion's World Wide Words where he points out that many good writers have used the much-maligned now-grudgingly-accepted "than".