Pros
I just joined Salesforce.com, and my experience has been excellent in every way. The onboarding process has been a breeze because the company uses the tools they sell which allows new hires to get up and running quickly. Specifically, the company uses Chatter groups where employees can find virtually all the information they need for any questions and get immediate responses, rather than spending 6 months trying to find out "who does what" within their new company. Furthermore, everybody I speak with seems to love working here and the company culture is very positive and supportive of employee success.
Cons
The only con is that I work from home and miss the social aspect of going into an office, but the collaboration tools Salesforce provides makes it easy to connect with other employees.