So far, so good. Sort of.
He has officially outgrown the use of his playmat due to increase mobility (twice so far I've found him wedged under the ottoman). So in order to avoid a visit from child welfare, I decided to pull out the playpen. According to my Mommy and Me guru Sophie, if I want to contain him when he starts crawling, I'll need to put him in some sort of containment contraption before the fact, or else he'll protest the confinement.
The novelty has obviously not worn off yet.