Pros
A true meritocracy, Wayfair encourages all employees to share their ideas and contribute to make the company succeed. There's great access to senior leadership, plenty of networking and social opportunities (after-work panels, sports leagues, volunteering opportunities, etc.), and a ton of responsibility from day one. The new office space in the Copley Place Mall is beautiful, with open seating, gorgeous Wayfair products, and plenty of conference room/break room spaces. The company is growing like crazy (just look at the quarterly earning statements), so it's truly a once-in-a-lifetime opportunity right now. There aren't a lot of other companies that are public, growing at a similar rate, and that have the market cap that Wayfair has. As it continues to open more offices and grow teams, opportunities abound.
Cons
There aren't a lot, as long as you're a self-starter. Wayfair doesn't do a lot of hand-holding, so if you're looking for automatic promotions, career paths that are spelled out for you, or other things like that, you may be a bit disappointed. Additionally, internal planning still leaves something to be desired. The company's growing really fast, and that's great; but sometimes things get overlooked and we need to play catch up to accommodate that growth. It can be frustrating, but in a lot of ways, that's what makes it fun and exciting, too.