This is at least better than the previous calibration image, but what's to come, post calibration, is going to knock our socks off. I would save your money for a yet-to-come poster. I'll probably buy one too.

Basically, what they've done is point JWST at a nearby-ish star, which we'd characterized already in terms of brightness (both absolute and relative magnitude) and spectral signature. Because of how yuge the mirror(s) is, I doubt much time at all was required to collect the many photons that makes the star appear so bright, and even to reveal those galaxies. Due to its smaller mirrors, Hubble would require much more time (at least a factor of ~10) to collect the same amount of photons. But yeah, now the JWST peeps are dialing in their ground-support image processing software side to help eliminate non-physical artifacts like the six spikes emanating out from the star, and separate out individual wavelengths using the star they're calibrating to.

Everyone seems to be most excited for imaging nearby exoplanets, but I cannot wait for the edge-of-the-visible-universe, galaxy-formation-stage cosmological insights that JWST will provide. Big hype!!