Ventajas
As far as large corporations go, the average quality of the people working there is still high. Despite the shocking growth, the hiring standards in the core groups are still high. The company generally treats employees generously. Few companies have operating systems, data centers, a video game console, a music player, web advertising and content properties, database management systems, word procesing, spreadsheet and presentation and generally everything else. The discipline that comes from working on products that millions already use - the constraints and the candid feedback - are humbling and highly educational. The benefits are excellent. And if you are at all in the outdoors, the Pacific Northwest is stunning.
Desventajas
A large, centralized campus in the suburb of a mid-size city results in a fair amount of insularity, especially when such a large number of employees are hired out of college and have not worked anywhere else. Only in such an environment do people believe tagging a web site with 'Windows' - e.g. 'Windows Live' - to be a plus for branding. As the company ages and grows, it requires more organizational overhead, which, combined with the kind of orderly processes required to ship products like Office to hundreds of millions of users in dozens of languages, does not result in an agile, entrepreneurial environment. Compensation has, for all practical intents and purposes, stalled. You can get richer there than you'd be at IBM but the gap is shrinking.