Pros
Company is leading edge in technology, the future. Generally successful in attracting high quality staff, low to high. They pay well and if you joined early enough, your options could deliver a nice nest egg. Whether or not you agree with your goals and targets, they are typically well communicated.
Kontras
If you're an ex-colleague of anyone on the sr leadership team you may be allowed the benefits inside the bubble. For everyone else: you will be digging for gold dust and hopefully be deemed ok. This company should be avoided if you think on your feet and are proactive. Employees will be asked to respond to every whim of their manager and smile while running out to comply. All the bling outside charisma of the 'startup' culture doesn't mean a thing... The culture is mostly corporate, risk averse and set in 50 shades of grey. Customers are treated well before signing, and pretty much ignored until they raise their hand. It all could have been so much better but I feel ServiceNow has missed the opportunity to build a great company. Shareholders won't mind in the short run.