An alert reader posted on a 23andMe forum thread (!) that the AncestryDNA drop-down list for filtering now includes a choice to see just the records with a leaf tip. I have two.
There is another match that should get a leaf tip since it goes back to the same ancestral couple as one of the two. I'd would guess that the addition of leaf tips is done on a rolling cycle basis, so I'll check back again every now and then.