Pros
As a current employee of Guidewire I am very proud to be affiliated with this company, and extremely bullish about the company's future. We have a very flat organizational structure on the development side, which ensures that all voices and opinions are heard and our concerns with regard to schedule are factored into all release planning. The flat structure also allows for people to step up where they see a need and act to fill that need. After 8 years, the founders are still very involved with the day to day operations (for example, the CTO writes code on a regular basis). The company has a great tradition of internal and external transparency. Management shares extensive details about company financials, sales pipeline and other critical topics at quarterly meetings. The external transparency is evidenced in how sales and management deal with current and prospective customers, always telling the truth even when it's not going to be popular.
Cons
Not the greatest benefits package. Specifically, no match on the 401(k), and none planned until after a future IPO. In general the management is very frugal, bordering on cheap. On the plus side this has helped the company to surf the economic tsunami successfully and remain in a very strong market position, but a 401k match would be nice.