Pros
One of the few aerospace companies left in the US. Boeing is a large, and complex, so there many different technical or business opportunities (within aerospace or defense). Boeing is also the main player in global aviation, so there a plenty of international opportunities.
Cons
The best part of the "old" culture is being tossed out, and yet retained the it's worst business practices. Most specifically, there is to much "dead weight" within Boeing. People who exist without any consideration of business practices in any other part of industry. Mainly Boeing is too bureaucratic. When I arrived a coworker described it as similar to working for the government ... which is about right. The other big issue is a lack of excellence in engineering - I believe this is mostly due to their culture of promoting seniority (even if it is a non-degreed drafter) over talent.