Pros
Working for Nielsen gives great experience across the CPG Industry. With regard to 'soft benefits' - they do support a work-from-home environment and they do much to promote a healthy lifestyle. I do believe their base pay & benefits (i.e., vacation time, vision insurance, etc...) to be above average.
Cons
The company offers great career and promotional opportunities (and merit increases) for the top 10%. The balance really don't get much. The balance get moved around to fill holes with pay raises of 2-3% every one to two years. They have become too bottom-line oriented and thus provide less through bonuses every year, send more work offshore, and continue to replace tenured employees with lower priced, more junior level hires. If you're not "a star" and just a solid performer - your opportunities will be limited.