Technically there is no such thing as a "loadcenter". What our trade calls loadcenters are still UL Listed as panelboards. The residential/commercial loadcenter is really nothing more than a marketing phrase.
Some manufacturer have large differences between their loadcenters and panelboards. They then create pricing and marketing to exploit these differences. This marketing has caused many electricians and, sadly, inspectors to believe there are restricted use issues with loadcenters.
First you must always follow the job specification, but after that the NEC doesn't care what the panel is called as long as it is an NRTL Listed panelboard.
In reality, the biggest difference between loadcenters and panelboards is the enclosure.
Panelboards enclosures usually included NEMA 12 and NEMA4/4X enclosures as well as the NEMA1 and NEMA3R offered in loadcenters.
Loadcenter back boxes are usually designed to fit inside the stud space of standard 2x4 wood frame construction and include knockouts located "conviently" for NM cable. Panelboard boxes are designed wider and deeper with very few knockouts to allow for many more conduit entrances.
Other than the enclosure and factory installed options, the differences can be very subtle, but it depends on the manufacturer. My experience has been that there are only a few general panelboard specs that are not offered in any loadcenter (i.e. bolt-on breakers).
For design and build projects, I have always based my choice of a Square D QO loadcenter or NQOD panelboard primarily on mounting and wiring considerations.