Google may or may not have higher employee satisfaction, but I sure wouldn't trust Glassdoor to know. This is based on an anonymous 20 question survey of "at least 115 employees" at each company, so you know that one of the two data sets only numbers 115 responses, implying a best-case response rate of 3.8% (Facebook at an estimated 3K employees). There is no information on how the sample set is gathered. Was it self selecting? What type of employees were consulted? Did they span management, or were they all individual contributors? How much can you really learn in 20 questions?

Furthermore, the "best tech company to work for list" that is linked in the article (http://www.zdnet.com/blog/facebook/facebook-named-best-tech-...) is another Glassdoor list, and a highly suspicious one at that. I compared it to the corresponding CNN/Fortune list (http://money.cnn.com/magazines/fortune/best-companies/2012/f...), and out of the top 10 companies on the Glassdoor list, only 3 were on the top 100 Fortune list: Google, Facebook and REI. I've never even heard of 4 of the other 7, including the top 2, and of those 7, 5 aren't even on the CNN/Forbes top 100. On top of all this, this is supposed to be a tech list and it's filled with companies like General Mills, Southwest Airlines, Starbucks, Coach and FedEx, not to mention the fact that the top 2 are also both business consultancy firms.

I could go on, but I think the trend is pretty clear. Glassdoor appears to be basing these ratings on very small (and probably self selecting) samples sizes, and doesn't appear to have a very good means of gathering data from the right companies. Considering it's a relatively new company, this feels like something they want to make big, but they just don't have the brand and sway to implement a well designed study/survey/what-have-you.

If your curious what the CNN/Fortune study's methodology is: http://money.cnn.com/magazines/fortune/best-companies/2012/f...