I'm beginning to feel like a broken CD here. There's an easy way to remember whether from or than is correct after different. Recast the sentence.

This group is different from that group.

This group is different than that group.

But if you recast the sentence, you have:

This group differs from that group.

or

This group differs than that group.

NO one I know would use "differs than." Not even my brother who passed the test to be a speed bump. And not even my other brother who failed the same test.


TEd