Vantaggi
There's nothing wrong with average. If you are average and like to be around people who are just like you or slightly below average, then Groupon is a great fit. There's a general lack of accountability to be a rockstar, so you'll have the opportunity to coast by doing "ok" work for an "ok" company. Punch in at 9:05am, punch out at 4:59pm. Don't create, don't ask hard questions about where the company is headed. If you're social and want to meet fun people, there are lots of young and fun people to befriend and partying to be had.
Svantaggi
All technology companies do is manufacture innovation. When technology companies stop innovating, their ability to grow shrinks and business performance suffers. To innovate, you need the best people. To attract and retain the best people, you need to foster an environment that drives creativity, innovation, and excellence. Groupon had this for a moment in time, but lost it, and lost a lot of A-level talent in the process. The end result is that the company has migrated to the mean. If you're serious about business and working in an environment where the culture allows you to stretch your thinking and imagination, look elsewhere.