There will obviously be differences between the current forums and the new - but change can be very positive and the pros absolutely outweigh the cons (very minor learning curve) of a change.
vBulletin was absolutely the best platform to get CF to where it is today - no question. But, it's basically EOL and hasn't been able to add the things people want and expect in 2016 (let alone in the future). It's also a security risk at this point.
Rather than continue to bolt on additional weight onto the current platform, the new platform will be able to keep the good without carrying the weight and baggage of everything else before it. People want integration, media, content, betting, speed, mobile, etc but all of that requires system resources, adds queries, and increases overhead to an already resource-heavy framework. vBulletin is like Windows 98 SP 2, a very bloated and antiquated solution that carries the dead weight of everything before it.
There will absolutely be differences in how to accomplish certain things, but there are usually workarounds for those that are either frequent or critical. Don't hate change just because it's different, treat this like the excitement of changing from the old football mentality and staff to the new.