Ipsos is a funny name for one of the oldest and largest global market research companies. They were founded in 1975 and if you follow US politics, you'll recognize them partnering often with Reuters to produce approval surveys of Congress, the President, and other notable figures. They're headquartered in Paris, France and publicly traded on the Paris Stock Exchange. They have revenues of over a billion dollars – Ipsos i-Say is just a small piece of their business.
You can expect to earn $2-$5 for most of the surveys in general. For some special surveys you can earn up to $50 per survey but those are rare. Harris Poll also conducts paid focus group studies where you can earn $50-$100 per study. Usually these focus group studies are 1-2 hours long where you interact with other participants under a supervision of a focus group moderator.
Paid survey site companies invest billions of dollars into marketing research online. They always want to find out more intricate details of a consumer's relationship with their product. Whether it's a new television show or just an existing product line, companies like Disney, Samsung, and Sony go to great lengths to find out their ideal audiences.