I the recent years, we saw a lot of interesting new features on wheelguns: High cap cylinders (up to 10 shots in 22lr now, 8rd .357 Mags etc.), polymer frames, built-in lasers, .410 shotshell chamberings etc.
High capacity is nothing new.
Shotgun calibers are nothing new, but never caught on until recently. As for the unique materials and add-ons such as lasers, they do modernized and sometimes improve an old concept. The question is whether the public wants such new features or not. Apparently at this time, many are indeed selling well.