I have accessed to the ServiceNow training services they offer. And as I have been using the SalesForce Trailhead services, to compare it is the first thing I have done.
The first thing you find is that the majority of the courses are so much expensive. You can consider that nothing is for free, but the amount of training courses offered by SalesForce is impressive.
The user interface is very classical in comparison with trailhead. The use of videos is low and there is a lot of documentation to read, but without a clear learning path or goal.
The way the information is updated it nice but you have the feeling you are accessing to a help database from 2002.
It’s clear the training strategy from ServiceNow is so much different to the one picked by SalesForce. I’m sure they are making some money with these training courses, but the speed of adoption of the communitty (technical, users and business users) is going to grow very slowly in comparison with SalesForce.