Well no change there then.
MS has never delivered anything, for free or not, that met consumer security needs.

Unfortunately the "average" user I don't think is really aware of the antivirus ratings and just buy what they are most familiar with. M$ uses this give away for "free" tactic all the time, unfortunaly with often good results. An average user might say why the heck spend $50 bucks on symantec or mcafee when it is free in Widows already. With the winds changing toward increased regulation I'm hoping regulators don't let them get away with such anti-competitive behavior.

Wouldn't this be considered an oxymoron?

And I agree with Deimios. Stop trying to cover the entire market MS and concentrate on giving consumers the better OS without the security holes or exploitable features and more of us will buy it.

If this is the same engine as the current Microsoft antivirus (that struggles to get a 'standard' rating on av-comparatives.org) then I say you're better off with Avira, Avast or AVG.

Also I doubt that anti trust regulators will appreciate the move. So lemme put it this way: You sell a boat that is full of holes. They you offer to fix some of the holes for free, while fixing more of the holes for extra money. Put your damn resources into making a boat that doesn't have holes!