Much has been written and disseminated about their culture, benefits and compensation practices. They are one of the largest software companies in the world with a publicly recognized name. Their product offerings span just about everything you would want to do with a computer. They have (historically) been a very stable source of employment, with a good compensation and benefit package, along with a full career path for developers (a rarity in most companies it seems).
Unfortunately, their business practices have also left some developers with a bad taste in their mouth (whether through their previously predatory nature, or their current lack of a cohesive approach to the web). Given that Microsoft is a well-known entity in the developer world (and frankly the larger US-culture), I will assume that you fall into on of those categories, in which case Microsoft will need much more than perks and salary (of which they apparently have many - I am not affiliated nor have I ever been affiliated with them) to sway you.
On the other hand, there are plenty of folks out there who may not have the same negative experiences with MS and, based on everything I said above, would consider the company an excellent place to work.