As of yesterday afternoon Oliver is no longer a quadruped.
He took his first steps a few days before Christmas. Then he would walk between Nick and I but not without real encouragement and prodding. Yesterday we were watching him in the living room and Nick said something to the effect of you should really just walk already! Well, strangely enough he did. I'm not kidding. O just looked at his dad almost to say, "fine, I will" and walked over to his activity table like it was nothing. If I hadn't seen it myself I wouldn't have believed it.
He's been walking all over the house since then and doing pretty well. He's still pretty wobbly and I'll say it's still not his primary mode of transportation but we're claiming that he's officially a walker. Here is a really short video for the family.