Good place to gain initial experience, but it can be difficult to further your career after that.
Pros
Talented and driven individuals compose the workforce at Micron. The company seems to currently be going though a transformation phase: Upper Management is actively focusing on improving on the various industry benchmarks where Micron lags behind the competition. They also understand the importance of moving away from a highly commoditized business model (sell a ton of generic memory), and into an style of business than caters more specifically to the customers solutions. If you want to move to Boise (Company HQs), you will love the city: no traffic, mild winters, no pollution, plenty of outdoor recreation, and much lower costs of living than the traditional high techs meccas (Silicon valley, etc.) I consider living here a much higher standard of living than in crowded and overpriced Northern Cal.
Cons
Like all large companies, bureaucracies can form that slow down progress. The company has a very talented pool of employees but the disjointed way in which different departments sometimes function can act as a hindrance to innovation. There seems to be a proliferation of empires built by middle managers. Career development opportunities can be scarce. Lateral moves are available but it can be challenging to find an opportunity to move up in the company.