Rock's Peony, Paeonia rockii or Paeonia suffruticosa ssp rockii is well along at this point. No flower buds in sight yet, but this species has not yet flowered for me here (the plants are fairly young).
Paeonia delavayi a few days along in the sprouting of its foliage buds, both from the root and on last year's wood.
Paeonia ludlowii not as far along; most of the buds are merely swelling a bit so far but a few have begun to sprout.
A bit further along is Paeonia x handel-mazzettii, a natural hybrid of the previous two.