Check this out! Windows Live OnceCare and Forefront Client Security have passed Virus Bulletins VB100 Award. This is in addition to already receiving the Checkmark Certification from West Coast Labs.
I for one run Forefront Client Security on all my machines at home and I find it works very well. I especially like the "green tick".
I would love to run it at home, but alas, it isnt on MSDN.