Its normal for puppies and some breeds to get hiccups regularly. Both of our dogs still occasionally get hiccups. Puppies tend to eat quickly and a consequence of that is swallowing a lot of air. Swallowing air can irritate the diaphragm and that is one of the causes of hiccups. So I would say its nothing to be concerned over and I would guess it gets better with time.
Levi started getting hiccups a couple weeks after we got her (2 1/2 months old). She used to hiccup often, but now hardly does. She still gets occasional hiccups (she's around 5 months now). Our vet told us it's normal for puppies to get the hiccups.