If you pay attention to the bike community, one of the hottest trends recently is the fat bike. Essentially anything that has a wheel of 3" or wider. They are designed to ride on sandy beaches and snowy trails. The wider wheel allows you use a smaller psi which allows you to slice threw elements that normally would be very difficult.
People say they are a blast to ride and it doesn't look like a trend that will leave anytime soon. The question I ask is, will it be good for the serious cyclist. Most sports, there is always an "off season." A time to restrengthen and realign and decompress from the previous competitive season. No sport runs 365.
An article I read awhile back showed that those that did cross country skiing when compared to other lifelong endurance athletes were about 40% fitter. If XC skiing was one of your off season workouts and you are switching to a fatbike, be prepared to be potentially less "injury proof," and less fit.
One of my other concerns, is though it can be viewed as a "strength component," when things get to specific to your trained movement it can cause mechanical changes. This is the reason you don't run with ankle weights or throw a weighted baseball. You don't want to let your legs get used to spinning at a lower cadence.
So if you choose to enjoy the fatbike, get some faster then normal cadence work in. Spend a few more mini sessions at home or the gym ironing out better movement patterns in the lunge, squat, push up.