Looks like this is yet another thing where teachers, those who know more technical things than lay users, native speakers, and learners all say different things.
One thing I've noticed since joining these forums is how much disagreement there really is in language. It's good in some ways, and certainly it's easy to say 'both of those are used a lot by native speakers', but to be an English teacher making an assessment of English! It must be rough!
I can imagine a student going to their English teacher, "No Mr. Blah, Linguist__ from UsingEnglish says your answer is wrong and that he hears it said that way where he lives, and blah_blah from UsingEnglish thanked his post, so he agrees"!!
As for this post, I think I'd say what bhaisahab said, which is the complete opposite to what 2006 said!
Of course, I'd really take the easy way out and say 'all of them are used, so they are all correct'.